## Why

Manual recordings started shortly before an appointment currently miss Outlook metadata, while concurrent appointments make automatic lookup ambiguous. Once an appointment-specific recording notification appears during an active recording, the user also has no way to attach that exact appointment's metadata without stopping the current meeting.

## What Changes

- Treat a Teams appointment that starts within five minutes after a manual recording begins as current for Outlook metadata enrichment.
- Keep standalone metadata lookup conservative when multiple in-progress appointments match, or when multiple appointments fall in the grace window and none is already in progress.
- When a calendar recording prompt is shown during an active recording, add an `Add metadata to current meeting` action below the existing affirmative and negative actions when the Windows notification layout permits it.
- Apply the prompted appointment's title, eligible attendees, agenda, and scheduled end to the active meeting without stopping or starting a recording.
- Reuse the normal attendee transformation and artifact-update behavior when prompted metadata is attached to an active meeting.

## Capabilities

### New Capabilities

None.

### Modified Capabilities

- `meeting-session`: Extend Outlook enrichment with a five-minute pre-start grace period and allow appointment-specific prompt metadata to be attached to an active meeting.

## Impact

- Outlook current-meeting candidate selection and its Windows provider.
- Calendar prompt scheduling, response contracts, and Windows toast layout/activation handling.
- The active recording controller/coordinator metadata update surface.
- Meeting-note, assistant-context, transcript metadata, and workflow behavior tests.