feat(frontend): add forgot-password and reset-password pages

- /forgot-password: email form → sends POST /api/auth/forgot-password → success banner
- /reset-password: password form reads token from URL → sends POST /api/auth/reset-password
- Login page: add "Passwort vergessen?" link
- hooks.server.ts: add /forgot-password and /reset-password to PUBLIC_PATHS; skip auth
  injection for public auth API endpoints
- errors.ts: add INVALID_RESET_TOKEN error code
- i18n: add all new message keys in de/en/es
- playwright.config.ts: use E2E_BASE_URL for webServer check URL (allows reusing docker
  dev server at port 5173 locally)
- ci.yml: pass E2E_BACKEND_URL=http://localhost:8080 to E2E test step
- e2e/password-reset.spec.ts: 5 tests (4 pass locally, full flow requires e2e profile in CI)
- Regenerated OpenAPI types including new /api/auth/* endpoints

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitea/workflows/ci.yml

@@ -190,6 +190,7 @@ jobs:
           E2E_BASE_URL: http://localhost:3000
           E2E_USERNAME: admin
           E2E_PASSWORD: admin123
+          E2E_BACKEND_URL: http://localhost:8080
 
       - name: Upload E2E results
         if: always()