Various QoL Improvements

[DaelonSuzuka]

• Updated Godot icons (and removed old ones)
• Improve "Debug Pinned Scene" command by making the pinned scene persist between VSCode sessions
• Fix scene file highlighting not working
• Fix ScenePreview not working in Godot 3
• Add buttons for relevant actions to ScenePreview items
• Add internal document links for SubResource() and ExtResource() statements in scene files
• Add hover for SubResource() and ExtResource() statements in scene files
• Improve ability to right click -> open docs for methods of builtin types (doesn't always work)
• Add a file decorator to show the pinned debug file in the filesystem view/editor tabs
• Add item decorators to the Scene Preview to show Node attributes more clearly
• Updated readme
• Overhauled documentation viewer
• Added GDScript formatter
• Add (disabled) experimental providers for custom completions, semantic tokens, and tasks

[DaelonSuzuka]

Big refactor of the docs manager:

• Added content caching: why did this extension re-request information from the LSP that it already had?
• split the page rerendering stuff into it own file, will make it easier to work on
• Added a minimap:

[DaelonSuzuka]

I've rewritten the documentation handler. The previous "Open Godot Documentation" context menu command has been removed, everything is handled via go-to-def and .gddoc custom file handling.

It works for me when I move the cursor with arrow keys and hit F12, so please let me know if there's any issues with your vim movements, @levidavidmurray

As a cool bonus, we get this behavior:

Because the documentation is now a virtual custom file, reloading the editor will cause vscode to automatically reload the docs, too (assuming that it connects to the LSP in a timely manner, of course).

[levidavidmurray]

It works for me when I move the cursor with arrow keys and hit F12, so please let me know if there's any issues with your vim movements, @levidavidmurray

@DaelonSuzuka No issues at all—it works perfectly! Thank you very much for all your hard work! 🚀

I'm curious if there's any reason the VSCode Marketplace extension hasn't been updated in over a year? Is the original publisher (Geequlim?) just not around to do it?

[DaelonSuzuka]

I've been working on the debugger for basically that entire time and hadn't managed to get anything polished enough to release. This PR is probably the last major item that's going into the next version, and I really want to get that out this week.

Your effort with testing and redesigning the go-to-def provider was actually a big help, so thanks again for that!