Add period logging endpoint that allows users to record their period start date.
This is a critical path item that unblocks GET /api/cycle/current and GET /api/today.
Features:
- Protected with withAuth middleware
- Validates startDate is present, valid format (YYYY-MM-DD), and not in future
- Updates user.lastPeriodDate in PocketBase
- Creates PeriodLog record for historical tracking
- Returns updated cycle information (cycleDay, phase)
Tests: 8 tests covering authentication, validation, database operations, and error handling.
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Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Petru Paler
62ad2e3d1a