Update auto-click functionality

[asahisuenaga]

This PR addresses and fixes several open issues with the extension. Let me know if there's anything else you need.

Additionally, I noticed this repository has been quiet recently. I completely understand that maintaining open-source projects takes significant time and effort. If you no longer wish to maintain the YouTube NonStop extension, I would be more than happy to step in and take over ownership or co-maintenance. I have successfully built and published several browser extensions myself, so I am highly familiar with the ecosystem.

Changes Made

• Addedytd-watch-flexy[player-unavailable] button[aria-label="I understand and wish to proceed"]every 2000ms
• Added a DOM MutationObserver
• Added a fallback setInterval check
• Clicks visible dialog buttons for both:
  • yt-confirm-dialog-renderer
  • ytd-watch-flexy[player-unavailable]
  • fallback [#confirm-button

Testing Instructions

1. Clone or download this branch.
2. Load the unpacked extension into your browser (chrome://extensions or about:debugging).