Add UI and functionality for managing disabled sites settings

[yanmuq]

Summary

This pull request adds a disabled-sites list to WebRTC Control.

The extension currently works globally, but some users need WebRTC Control to stay enabled by default while being disabled on specific sites. This change adds an options-page section where users can manage those sites without changing browser-level extension permissions.

Changes

• Adds a new options-page section: Sites where WebRTC Control is disabled
• Allows users to add, edit, and remove disabled site entries
• Stores the disabled-sites list in chrome.storage.local
• Skips page-context WebRTC blocking scripts on matching sites
• Temporarily restores the browser WebRTC policy to default when the active tab matches a disabled site
• Adds the tabs permission so the extension can detect the active tab URL
• Bumps the extension version to 0.3.5

Matching behavior

Entries are matched by hostname. Supported examples:

example.com
www.example.com
*.example.com
https://example.com/path
URL entries are normalized to their hostname.

Note
Chrome's webRTCIPHandlingPolicy setting is global rather than per-site. Because of that, this implementation restores the WebRTC policy based on the active tab. When the user switches away from a disabled site, the configured protection policy is applied again.

Testing
Checked JavaScript syntax with node --check
Parsed manifest.json successfully