Amplifier Unified 0.34.12

Keep background notices from slowing down large chat libraries

Changes

• Prepare unread counts and review notices without scanning unrelated imported chats. This removes a repeated source of delays in chat loading, app actions and streamed updates as saved history grows. Current titles, read markers, hidden chats and review behavior remain unchanged.
• Add a regression check that grows the imported-chat catalog independently of the notice list, so a small response cannot hide an expensive full-catalog query. Release workflows also pin their GitHub Actions to reviewed source revisions.