feat: add Plex authentification

[zdimension]

Description

Adds a setting that allows requiring Plex authentication to access the web UI. This is useful especially if the user wants to expose the web UI to the outside world.

Screenshot

Issues Fixed or Closed

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Dependency update (updates to dependencies)
• Documentation update (changes to documentation)
• Repository update (changes to repository files, e.g. .github/...)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have added or updated the in code docstring/documentation-blocks for new or existing methods/components

Branch Updates

LizardByte requires that branches be up-to-date before merging. This means that after any PR is merged, this branch
must be updated before it can be merged. You must also
Allow edits from maintainers.

• I want maintainers to keep my branch updated

[codecov]

Codecov Report

Attention: Patch coverage is 66.12903% with 21 lines in your changes missing coverage. Please review.

Project coverage is 66.43%. Comparing base (6ccf241) to head (ab60056).

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #229      +/-   ##
==========================================
- Coverage   71.84%   66.43%   -5.42%     
==========================================
  Files          12       12              
  Lines        1087     1147      +60     
==========================================
- Hits          781      762      -19     
- Misses        306      385      +79     

Flag	Coverage Δ
Linux	66.34% <64.51%> (-5.14%)	⬇️
Windows	65.91% <56.45%> (-5.58%)	⬇️
macOS	66.34% <64.51%> (-5.51%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
Contents/Code/default_prefs.py	100.00% <ø> (ø)
Contents/Code/plex_api_helper.py	50.58% <100.00%> (-2.75%)	⬇️
Contents/Code/webapp.py	59.04% <59.61%> (-9.08%)	⬇️

... and 3 files with indirect coverage changes

[ReenigneArcher]

Any thoughts on unit/functional tests?

[LizardByte-bot]

It looks like this PR has been idle for 90 days. If it's still something you're working on or would like to pursue, please leave a comment or update your branch. Otherwise, we'll be closing this PR in 10 days to reduce our backlog. Thanks!

[zdimension]

It looks like this PR has been idle for 90 days. If it's still something you're working on or would like to pursue, please leave a comment or update your branch. Otherwise, we'll be closing this PR in 10 days to reduce our backlog. Thanks!

Not really sure what more I can do here, we were discussing testing at one point but I don't really know how I would go about testing this

[ReenigneArcher]

Would you be okay with me pushing some commits to handle the testing?

[zdimension]

Would you be okay with me pushing some commits to handle the testing?

Absolutely, thanks!

[ReenigneArcher]

I think unit tests were pretty close, but held up by the following:

• fix(yt-dl): validate audio url and add retry logic #486
• build(deps-dev): bump plexhints from 2023.1211.160853 to 2024.726.1720 #482