Fixes WhatsApp Web privacy blur coverage for the active chat header and chat-row/profile avatars.

Changes:
- Blur active chat header name/status and avatar reliably, including reused header DOM\n- Blur profile/sender avatars adjacent to message bubbles
- Keep hover reveal/reblur behavior for sidebar, header, drawer, and messages
- Restore and verify extension options/config hot reload
- Add jsdom tests for blur behavior and options toggles