meeting-assistant/openspec/changes/add-recording-inactivity-safeguard/tasks.md

Implementation

• Add inactivity safeguard configuration.
• Add prompt service abstraction with Windows and no-op implementations.
• Use native Windows app notifications with action buttons for Windows prompts.
• Track last text transcript arrival and last transcript timestamp on active recording runs.
• Prompt at configured inactivity thresholds and auto-stop at the configured threshold.
• Use inferred end time for safeguard-triggered normal stops.
• Add focused behavior tests.
• Validate with dotnet test MeetingAssistant.slnx and openspec validate add-recording-inactivity-safeguard --strict.