feat: fix and improve auto-selection for default dubbed audio language

[Pieko16]

Description

This PR fixes the issue where the "Default Dubbed Language" setting failed to automatically switch the video's audio track.

Technical Root Cause

The previous implementation was attempting to read languageCode from the getLanguageInfo() object. Through debugging, it was discovered that YouTube's Player API does not provide languageCode for audio tracks (it is only available for text/caption tracks). Audio tracks store their language identifiers in the id property (e.g., "en.1", "tr"). Because the code was looking for a non-existent property, the matching logic always failed.

Changes & Improvements

• Property Fix: Switched from info.languageCode to info.id to correctly identify the track language.
• Enhanced Matching: Updated the logic to handle various ID formats (e.g., exact matches like en or prefixed IDs like en.1 and en-US).
• Reliable Timing (Polling): Replaced static setTimeout calls with a setInterval polling mechanism. It now attempts to switch the track every 300ms (up to 10 tries) to ensure the player is fully initialized and tracks are loaded.
• Efficiency: Added an early exit check if only one audio track is available (meaning no dubbing is present for the video).
• Code Cleanup: Refactored the trySelectTrack function for better stability and error handling.

Linked Issue

Fixes #3747

[ImprovedTube]

hi and thank you so much! @Pieko16

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Sorry using our menu was or appeared comparably complicated here
https://github.com/code-charity/youtube/wiki/Contributing#adding-a-feature

We should document what is 'player_' for or don't need it.

'disabled' can automatically remove the variable from storage

(Please consider to come back in future, a follow up PR or so.)