[Marc-André Moreau (mamoreau-devolutions)]

Summary

• Detects prolonged silence independently for system audio and microphone recordings.
• Shows an amber warning on the affected source, with a persistent indicator in the minimized toolbar.
• Warns after five seconds without meaningful audio and clears when sound returns.
• Adds regression coverage for warning timing, threshold/recovery, pause/reset behavior, and source-specific notices.

Validation

• cargo test -p jiffshot-workflow (33 passed)
• cargo check -p jiffshot`n- Scoped Clippy passed with existing chunks_exact_to_as_chunks and ype_complexity lints allowed.