Varia: download ældre versioner

- New torrent backend (libtorrent), leading to a way better torrenting experience
- Video downloader backend overhauls for better performance and less issues

- #273
- #272
- #269
- (Browser Extension) Improvements to the extension to better handle download transfers.

- Ability to download playlists through the same Video/Audio functionality
- Ability to select individual files and folders to download through torrenting
- Option to dynamically send browser cookies through the browser extension upon each download (separate from cookies.txt file import support)

- Option to automatically extract downloaded archives
- Inclusion of the Deno JavaScript engine as required by yt-dlp
- Newly added tooltip text for various options and better keyboard navigation to improve accessibility
- The scheduler is now much more reliable
- Paused downloads show their download percentages when reloaded upon app startup before resume
- Download details window layout no longer breaks with very long URLs
- New languages: Hebrew and Cornish
- (Snap version) The tray icon on Snap is fully functional
- (Mac version) Initial experimental release on macOS

- Fix for Windows where 7z wouldn't be included
- Fix where Varia wouldn't automatically start in background mode
- Better handling of external processes like aria2c and tray to minimize the possibility of having a zombie process left running if Varia crashes
- Notifications are now shown on Windows and macOS
- seeecret way to enable server side decorations on Linux

- New download details window added for details like individual download speed, torrent peers etc.
- New open file button added for completed downloads.
- Retrying failed downloads is now more reliable.

- Minor bugfix and translations update.

- Video downloads now can be added through the browser extension.
- .torrent files can now be opened through a file manager.
- Magnet links can now be opened through a browser.
- "Checking video" dialog can now be cancelled.
- Download segments can now be adjusted through preferences. (contribution by @N0tACyb0rg)
- Scheduler config screen is now more compact and works better on smaller window sizes.
- Better crash handling.
- (Windows only) Dialog windows now properly grey out what's behind them for better legibility.

This release only involves the Windows (Installer) version as it fixes an issue that stops the "Update available" banner from appearing. Windows (Portable) and Linux versions aren't affected.

- Tray icon support.
- New option to automatically start Varia upon bootup.
- Bug fix: Pause All button malfunctioning
- Additional text and translations.
Special thanks to @N0tACyb0rg for playing a key role in finally getting tray icon functionality merged after all this time, and also on getting the start on bootup option PR rolling.
Also thanks to all contributors on Weblate for providing translations.

- Windows only: Varia now uses native window decorations for better integration and stability.
- New safeguards against having the aria2c process keep running in the case of a crash.
- Slight UI tweaks. The header bar also now shows the amount of downloads, and how many are completed.
- Updates to translations.

Many bug fixes, especially regarding the video download functionality, for overall stability.
Better multi-connection handling through aria2.
New retry button for failed downloads.
Twitch VOD downloads now possible. Video downloads now also respect the Remote Timestamp option.
Torrenting can now be entirely disabled.
yt-dlp backend updated to newer version with fix for YouTube downloads.