Adds ability to filter recordings by time windows after a configurable
retention period. Useful for reducing storage while keeping recordings
during relevant times (e.g., business hours).
New config options under record.motion (and record.continuous):
- days: maximum retention in days (null for unlimited, 0 for none)
- hours: list of time windows like "mon-fri 07:00-18:00"
- always_retain: hours to keep all recordings before filtering (default 24)
Recordings associated with alerts/detections are always retained
regardless of time windows.
