Sentry improvements: context, tracing, source maps, privacy manifest

- Set Sentry user context (id, username) in Journal root for all routes
- Tag Planner errors with session_id
- Use reactRouterV7BrowserTracingIntegration for route-aware traces
- Hidden source maps (no sourceMappingURL in bundles, .map deleted after
  upload to Sentry)
- Privacy manifest at /privacy documenting all data collection
- robots.txt blocking all bots on both apps
- Suppress i18next promotional console log

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/i18n/src/index.ts

@@ -23,6 +23,7 @@ export function initI18n() {
       interpolation: {
         escapeValue: false,
       },
+      showSupportNotice: false,
     });
 }