Swap from ForkAwesome 1.2.0 to FontAwesome 6.5.1. (#882)

### Prerequisites

Put an `x` into the box(es) that apply:

- [x] This pull request fixes a bug.
- [x] This pull request adds a feature.
- [x] This pull request introduces breaking change.

### Description

This change allows FontAwesome 6.5.1 to be used as a drop-in replacement
for ForkAwesome 1.2.0.

The easiest way to see that my change has worked practically-invisibly
is that the home page of the demo site now shows Medium with its new
three-circular-blobs logo instead of the old capital-M logo, despite the
fact I have not changed anything about the hugo configuration for the
demo site.

Points of note here:

- Using FontAwesome in SCSS is different. Therefore the ONLY breaking
change here is for people who have made changes to the theme and written
"@include fa-icon" in their SCSS. Everything that can happen in content
(e.g. class names) are translated by the v4-shims.
- All files here are from https://fontawesome.com/download ('Free for
Web').
  - The contents of the /scss folder are in assets/scss/font-awesome.
- The contents of /webfonts are in static/fonts (except
fa-v4compatibility because that's not needed - v4-shims does all the
work we need).
- /LICENSE.txt is added to both directories to ensure it is clear both
are part of the FA-licensed code.
- In ForkAwesome, the path to the font was constructed in _path.css
suffixing $fa-version, so the preload needed to have the version at the
end. Since the default behaviour of FontAwesome is to not include a
version suffix, the preloads no longer have one either. This is a
necessary change because the HTML spec (section 4.6.6.19) explicitly
says that the entire URL [i.e. including query and fragment] is in the
key used to determine whether an element in the preload cache can be
consumed.

### Issues Resolved

#858 

### Checklist

Put an `x` into the box(es) that apply:

#### General

- [x] Describe what changes are being made
- [x] Explain why and how the changes were necessary and implemented
respectively
- [x] Reference issue with `#<ISSUE_NO>` if applicable

#### Resources

- [x] If you have changed any SCSS code, run `make release` to
regenerate all CSS files

#### Contributors

- [x] Add yourself to `CONTRIBUTORS.md` if you aren't on it already

Co-authored-by: Luiz F. A. de Prá <luizdepra@users.noreply.github.com>

assets/scss/_content.scss

@@ -22,7 +22,8 @@
 
   article {
     a:where(.external-link)::after {
-      @include fa-icon;
+      @extend %fa-icon;
+      @extend .fa-solid;
       content: fa-content($fa-var-external-link);
       padding-left: 0.5em;
       font-size: 0.75em;

assets/scss/_variables.scss

@@ -59,3 +59,6 @@ $bg-color-notice-warning-content: #ffca281a !default;
 $fg-color-notice-error-icon: #e53935 !default;
 $bg-color-notice-error-title: #f443361a !default;
 $bg-color-notice-error-content: #ef53501a !default;
+
+// Path to FontAwesome TTF/WOFF files.
+$fa-font-path: "../fonts" !default;

assets/scss/coder.scss

@@ -1,6 +1,10 @@
 @import "css/normalize";
-@import "fork-awesome/fork-awesome";
 @import "variables";
+@import "font-awesome/fontawesome";
+@import "font-awesome/regular";
+@import "font-awesome/solid";
+@import "font-awesome/brands";
+@import "font-awesome/v4-shims";
 @import "base";
 @import "content";
 @import "notices";

assets/scss/font-awesome/LICENSE.txt

@@ -0,0 +1,165 @@
+Fonticons, Inc. (https://fontawesome.com)
+
+--------------------------------------------------------------------------------
+
+Font Awesome Free License
+
+Font Awesome Free is free, open source, and GPL friendly. You can use it for
+commercial projects, open source projects, or really almost whatever you want.
+Full Font Awesome Free license: https://fontawesome.com/license/free.
+
+--------------------------------------------------------------------------------
+
+# Icons: CC BY 4.0 License (https://creativecommons.org/licenses/by/4.0/)
+
+The Font Awesome Free download is licensed under a Creative Commons
+Attribution 4.0 International License and applies to all icons packaged
+as SVG and JS file types.
+
+--------------------------------------------------------------------------------
+
+# Fonts: SIL OFL 1.1 License
+
+In the Font Awesome Free download, the SIL OFL license applies to all icons
+packaged as web and desktop font files.
+
+Copyright (c) 2023 Fonticons, Inc. (https://fontawesome.com)
+with Reserved Font Name: "Font Awesome".
+
+This Font Software is licensed under the SIL Open Font License, Version 1.1.
+This license is copied below, and is also available with a FAQ at:
+http://scripts.sil.org/OFL
+
+SIL OPEN FONT LICENSE
+Version 1.1 - 26 February 2007
+
+PREAMBLE
+The goals of the Open Font License (OFL) are to stimulate worldwide
+development of collaborative font projects, to support the font creation
+efforts of academic and linguistic communities, and to provide a free and
+open framework in which fonts may be shared and improved in partnership
+with others.
+
+The OFL allows the licensed fonts to be used, studied, modified and
+redistributed freely as long as they are not sold by themselves. The
+fonts, including any derivative works, can be bundled, embedded,
+redistributed and/or sold with any software provided that any reserved
+names are not used by derivative works. The fonts and derivatives,
+however, cannot be released under any other type of license. The
+requirement for fonts to remain under this license does not apply
+to any document created using the fonts or their derivatives.
+
+DEFINITIONS
+"Font Software" refers to the set of files released by the Copyright
+Holder(s) under this license and clearly marked as such. This may
+include source files, build scripts and documentation.
+
+"Reserved Font Name" refers to any names specified as such after the
+copyright statement(s).
+
+"Original Version" refers to the collection of Font Software components as
+distributed by the Copyright Holder(s).
+
+"Modified Version" refers to any derivative made by adding to, deleting,
+or substituting — in part or in whole — any of the components of the
+Original Version, by changing formats or by porting the Font Software to a
+new environment.
+
+"Author" refers to any designer, engineer, programmer, technical
+writer or other person who contributed to the Font Software.
+
+PERMISSION & CONDITIONS
+Permission is hereby granted, free of charge, to any person obtaining
+a copy of the Font Software, to use, study, copy, merge, embed, modify,
+redistribute, and sell modified and unmodified copies of the Font
+Software, subject to the following conditions:
+
+1) Neither the Font Software nor any of its individual components,
+in Original or Modified Versions, may be sold by itself.
+
+2) Original or Modified Versions of the Font Software may be bundled,
+redistributed and/or sold with any software, provided that each copy
+contains the above copyright notice and this license. These can be
+included either as stand-alone text files, human-readable headers or
+in the appropriate machine-readable metadata fields within text or
+binary files as long as those fields can be easily viewed by the user.
+
+3) No Modified Version of the Font Software may use the Reserved Font
+Name(s) unless explicit written permission is granted by the corresponding
+Copyright Holder. This restriction only applies to the primary font name as
+presented to the users.
+
+4) The name(s) of the Copyright Holder(s) or the Author(s) of the Font
+Software shall not be used to promote, endorse or advertise any
+Modified Version, except to acknowledge the contribution(s) of the
+Copyright Holder(s) and the Author(s) or with their explicit written
+permission.
+
+5) The Font Software, modified or unmodified, in part or in whole,
+must be distributed entirely under this license, and must not be
+distributed under any other license. The requirement for fonts to
+remain under this license does not apply to any document created
+using the Font Software.
+
+TERMINATION
+This license becomes null and void if any of the above conditions are
+not met.
+
+DISCLAIMER
+THE FONT SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT
+OF COPYRIGHT, PATENT, TRADEMARK, OR OTHER RIGHT. IN NO EVENT SHALL THE
+COPYRIGHT HOLDER BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+INCLUDING ANY GENERAL, SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL
+DAMAGES, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF THE USE OR INABILITY TO USE THE FONT SOFTWARE OR FROM
+OTHER DEALINGS IN THE FONT SOFTWARE.
+
+--------------------------------------------------------------------------------
+
+# Code: MIT License (https://opensource.org/licenses/MIT)
+
+In the Font Awesome Free download, the MIT license applies to all non-font and
+non-icon files.
+
+Copyright 2023 Fonticons, Inc.
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in the
+Software without restriction, including without limitation the rights to use, copy,
+modify, merge, publish, distribute, sublicense, and/or sell copies of the Software,
+and to permit persons to whom the Software is furnished to do so, subject to the
+following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+--------------------------------------------------------------------------------
+
+# Attribution
+
+Attribution is required by MIT, SIL OFL, and CC BY licenses. Downloaded Font
+Awesome Free files already contain embedded comments with sufficient
+attribution, so you shouldn't need to do anything additional when using these
+files normally.
+
+We've kept attribution comments terse, so we ask that you do not actively work
+to remove them from files, especially code. They're a great way for folks to
+learn about Font Awesome.
+
+--------------------------------------------------------------------------------
+
+# Brand Icons
+
+All brand icons are trademarks of their respective owners. The use of these
+trademarks does not indicate endorsement of the trademark holder by Font
+Awesome, nor vice versa. **Please do not use brand logos for any purpose except
+to represent the company, product, or service to which they refer.**

assets/scss/font-awesome/_animated.scss

@@ -0,0 +1,153 @@
+// animating icons
+// --------------------------
+
+.#{$fa-css-prefix}-beat {
+  animation-name: #{$fa-css-prefix}-beat;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, ease-in-out);
+}
+
+.#{$fa-css-prefix}-bounce {
+  animation-name: #{$fa-css-prefix}-bounce;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, cubic-bezier(0.280, 0.840, 0.420, 1));
+}
+
+.#{$fa-css-prefix}-fade {
+  animation-name: #{$fa-css-prefix}-fade;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, cubic-bezier(.4,0,.6,1));
+}
+
+.#{$fa-css-prefix}-beat-fade {
+  animation-name: #{$fa-css-prefix}-beat-fade;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, cubic-bezier(.4,0,.6,1));
+}
+
+.#{$fa-css-prefix}-flip {
+  animation-name: #{$fa-css-prefix}-flip;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, ease-in-out);
+}
+
+.#{$fa-css-prefix}-shake {
+  animation-name: #{$fa-css-prefix}-shake;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, linear);
+}
+
+.#{$fa-css-prefix}-spin {
+  animation-name: #{$fa-css-prefix}-spin;
+  animation-delay: var(--#{$fa-css-prefix}-animation-delay, 0s);
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 2s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, linear);
+}
+
+.#{$fa-css-prefix}-spin-reverse {
+  --#{$fa-css-prefix}-animation-direction: reverse;
+}
+
+.#{$fa-css-prefix}-pulse,
+.#{$fa-css-prefix}-spin-pulse {
+  animation-name: #{$fa-css-prefix}-spin;
+  animation-direction: var(--#{$fa-css-prefix}-animation-direction, normal);
+  animation-duration: var(--#{$fa-css-prefix}-animation-duration, 1s);
+  animation-iteration-count: var(--#{$fa-css-prefix}-animation-iteration-count, infinite);
+  animation-timing-function: var(--#{$fa-css-prefix}-animation-timing, steps(8));
+}
+
+// if agent or operating system prefers reduced motion, disable animations
+// see: https://www.smashingmagazine.com/2020/09/design-reduced-motion-sensitivities/
+// see: https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-reduced-motion
+@media (prefers-reduced-motion: reduce) {
+  .#{$fa-css-prefix}-beat,
+  .#{$fa-css-prefix}-bounce,
+  .#{$fa-css-prefix}-fade,
+  .#{$fa-css-prefix}-beat-fade,
+  .#{$fa-css-prefix}-flip,
+  .#{$fa-css-prefix}-pulse,
+  .#{$fa-css-prefix}-shake,
+  .#{$fa-css-prefix}-spin,
+  .#{$fa-css-prefix}-spin-pulse {
+    animation-delay: -1ms;
+    animation-duration: 1ms;
+    animation-iteration-count: 1;
+    transition-delay: 0s;
+    transition-duration: 0s;
+  }
+}
+
+@keyframes #{$fa-css-prefix}-beat {
+  0%, 90% { transform: scale(1); }
+  45% { transform: scale(var(--#{$fa-css-prefix}-beat-scale, 1.25)); }
+}
+
+@keyframes #{$fa-css-prefix}-bounce {
+  0%   { transform: scale(1,1) translateY(0); }
+  10%  { transform: scale(var(--#{$fa-css-prefix}-bounce-start-scale-x, 1.1),var(--#{$fa-css-prefix}-bounce-start-scale-y, 0.9)) translateY(0); }
+  30%  { transform: scale(var(--#{$fa-css-prefix}-bounce-jump-scale-x, 0.9),var(--#{$fa-css-prefix}-bounce-jump-scale-y, 1.1)) translateY(var(--#{$fa-css-prefix}-bounce-height, -0.5em)); }
+  50%  { transform: scale(var(--#{$fa-css-prefix}-bounce-land-scale-x, 1.05),var(--#{$fa-css-prefix}-bounce-land-scale-y, 0.95)) translateY(0); }
+  57%  { transform: scale(1,1) translateY(var(--#{$fa-css-prefix}-bounce-rebound, -0.125em)); }
+  64%  { transform: scale(1,1) translateY(0); }
+  100% { transform: scale(1,1) translateY(0); }
+}
+
+@keyframes #{$fa-css-prefix}-fade {
+  50% { opacity: var(--#{$fa-css-prefix}-fade-opacity, 0.4); }
+}
+
+@keyframes #{$fa-css-prefix}-beat-fade {
+  0%, 100% {
+    opacity: var(--#{$fa-css-prefix}-beat-fade-opacity, 0.4);
+    transform: scale(1);
+  }
+  50% {
+    opacity: 1;
+    transform: scale(var(--#{$fa-css-prefix}-beat-fade-scale, 1.125));
+  }
+}
+
+@keyframes #{$fa-css-prefix}-flip {
+  50% {
+    transform: rotate3d(var(--#{$fa-css-prefix}-flip-x, 0), var(--#{$fa-css-prefix}-flip-y, 1), var(--#{$fa-css-prefix}-flip-z, 0), var(--#{$fa-css-prefix}-flip-angle, -180deg));
+  }
+}
+
+@keyframes #{$fa-css-prefix}-shake {
+  0% { transform: rotate(-15deg); }
+  4% { transform: rotate(15deg); }
+  8%, 24% { transform: rotate(-18deg); }
+  12%, 28% { transform: rotate(18deg); }
+  16% { transform: rotate(-22deg); }
+  20% { transform: rotate(22deg); }
+  32% { transform: rotate(-12deg); }
+  36% { transform: rotate(12deg); }
+  40%, 100% { transform: rotate(0deg); }
+}
+
+@keyframes #{$fa-css-prefix}-spin {
+  0% { transform: rotate(0deg); }
+  100% { transform: rotate(360deg); }
+}
+

assets/scss/font-awesome/_bordered-pulled.scss

@@ -0,0 +1,20 @@
+// bordered + pulled icons
+// -------------------------
+
+.#{$fa-css-prefix}-border {
+  border-color: var(--#{$fa-css-prefix}-border-color, #{$fa-border-color});
+  border-radius: var(--#{$fa-css-prefix}-border-radius, #{$fa-border-radius});
+  border-style: var(--#{$fa-css-prefix}-border-style, #{$fa-border-style});
+  border-width: var(--#{$fa-css-prefix}-border-width, #{$fa-border-width});
+  padding: var(--#{$fa-css-prefix}-border-padding, #{$fa-border-padding});
+}
+
+.#{$fa-css-prefix}-pull-left { 
+  float: left;
+  margin-right: var(--#{$fa-css-prefix}-pull-margin, #{$fa-pull-margin}); 
+}
+
+.#{$fa-css-prefix}-pull-right { 
+  float: right;
+  margin-left: var(--#{$fa-css-prefix}-pull-margin, #{$fa-pull-margin}); 
+}