Add 13 new E2E tests for period logging flow and calendar display

Period logging tests (5 new):
- Future date validation
- Cycle length display between periods
- Prediction accuracy display
- Delete period log from history
- Edit period log from history

Calendar tests (8 new):
- Today highlight in calendar view
- Phase colors in calendar days
- Phase legend display
- Today button for quick navigation
- Multi-month navigation with return to today
- Calendar URL generation
- URL format validation
- Copy to clipboard functionality

Total E2E tests: 113 (was 100)
Total unit tests: 1014 (51 test files)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

IMPLEMENTATION_PLAN.md

@@ -4,7 +4,7 @@ This file is maintained by Ralph. Run `./ralph-sandbox.sh plan 3` to generate ta
 
 ## Current State Summary
 
-### Overall Status: 1005 unit tests passing across 50 test files + 100 E2E tests across 12 files
+### Overall Status: 1014 unit tests passing across 51 test files + 113 E2E tests across 12 files
 
 ### Library Implementation
 | File | Status | Gap Analysis |
@@ -1107,15 +1107,15 @@ These items were identified during gap analysis and have been completed.
   - `e2e/auth.spec.ts` - 14 tests for login page, protected routes, public routes
   - `e2e/dashboard.spec.ts` - 24 tests for dashboard display, overrides, data panels, nutrition, and accessibility (expanded from 10 tests)
   - `e2e/settings.spec.ts` - 15 tests for settings and Garmin configuration
-  - `e2e/period-logging.spec.ts` - 9 tests for period history and API auth
-  - `e2e/calendar.spec.ts` - 13 tests for calendar view and ICS endpoints
+  - `e2e/period-logging.spec.ts` - 14 tests for period history, API auth, and period logging flow
+  - `e2e/calendar.spec.ts` - 21 tests for calendar view, ICS endpoints, and display features
   - `e2e/garmin.spec.ts` - 7 tests for Garmin connection and token management
   - `e2e/health.spec.ts` - 3 tests for health/observability endpoints (NEW)
   - `e2e/history.spec.ts` - 7 tests for history page (6 authenticated + 1 unauthenticated) (NEW)
   - `e2e/plan.spec.ts` - 7 tests for plan page (6 authenticated + 1 unauthenticated) (NEW)
   - `e2e/decision-engine.spec.ts` - 8 tests for decision engine (4 display + 4 override) (NEW)
   - `e2e/cycle.spec.ts` - 11 tests for cycle tracking (1 API + 4 display + 2 settings + 3 period logging + 1 calendar) (NEW)
-- **Total E2E Tests:** 100 tests (36 pass without auth, 64 skip when TEST_USER_EMAIL/TEST_USER_PASSWORD not set)
+- **Total E2E Tests:** 113 tests (36 pass without auth, 77 skip when TEST_USER_EMAIL/TEST_USER_PASSWORD not set)
 - **Test Categories:**
   - Unauthenticated flows: Login page UI, form validation, error handling, protected route redirects
   - Authenticated flows: Dashboard display, settings form, calendar navigation (requires test credentials)
@@ -1467,7 +1467,7 @@ This section outlines comprehensive e2e tests to cover the functionality describ
 6. `e2e/garmin.spec.ts` - +9 tests
 
 #### Total Test Count
-- **Current E2E tests**: 114 tests (UPDATED: 36 new tests + 14 dashboard expansion)
+- **Current E2E tests**: 113 tests (36 pass without auth + 77 with auth; includes period logging flow and calendar display tests)
 - **New tests needed**: ~102 tests
 - **Across 15 test files** (7 existing + 8 new)