feat: explore tab, React Query data layer, programs, sync, analytics, testing infrastructure

- Replace browse tab with Supabase-connected explore tab with filters
- Add React Query for data fetching with loading states
- Add 3 structured programs with weekly progression
- Add Supabase anonymous auth sync service
- Add PostHog analytics with screen tracking and events
- Add comprehensive test strategy (Vitest + Maestro E2E)
- Add RevenueCat subscription system with DEV simulation
- Add i18n translations for new screens (EN/FR/DE/ES)
- Add data deletion modal, sync consent modal
- Add assessment screen and program routes
- Add GitHub Actions CI workflow
- Update activity store with sync integration

.maestro/config.yaml

@@ -0,0 +1,17 @@
+# Maestro Configuration for TabataFit
+# https://maestro.mobile.dev/
+
+# App identifiers (iOS bundleIdentifier / Android package)
+appId: com.millianlmx.tabatafit
+
+# Default flows directory
+flows:
+  - .maestro/flows
+
+# Global settings
+defaultTimeout: 15000
+
+# Environment variables (override in .maestro/env.yaml)
+env:
+  TEST_USER_NAME: Test User
+  TEST_USER_EMAIL: test@example.com