chore: strip formatting noise, delete dead routes, fix CodeRabbit issues

- Remove 179 format-only file changes (docs, migrations, plex, patchmon, CSS)
- Delete .cursor/goal files from git tracking
- Delete 4 dead /api/about routes (unused, data loaded from static JSON)
- Fix resolveAlias to use absolute paths (CodeRabbit)
- Fix Tailwind classes in Mantine app layout fallback (CodeRabbit)
- Return stale data during cache revalidation (CodeRabbit)

packages/api/src/integration-data-cache.ts

@@ -24,7 +24,7 @@ export const getCachedIntegrationData = async <T>(
   const existing = cache.get(key) as CachedEntry<T> | undefined;
   const now = Date.now();
 
-  if (existing?.pending) return existing.pending;
+  if (existing?.pending) return existing.timestamp > 0 ? existing.data : existing.pending;
   if (existing && existing.timestamp > 0 && now - existing.timestamp < ttlMs) {
     return existing.data;
   }