Fixed recording state issues that could occur after multiple recording sessions.

Changes in this version:
- Fixed an issue where the Start and Stop buttons could remain disabled after recording more than once.
- Fixed an issue where the second recording could get stuck and could not be stopped.
- Fixed an issue where the countdown did not appear on some repeated recordings.
- Improved cleanup behavior when stopping or cancelling a recording.
- Added safer handling for recorder stop events to prevent the UI from staying blocked.
- Removed unsupported WAV and WebP output options from the extension build.
- General stability improvements for repeated recordings.