Remove backwards compatibility for API responses

- Clean up all backward compatibility checks for old API format
- All endpoints now consistently return { success: true, data: [...] }
- Simplify response handling across all components and pages

🤖 Generated with [Claude Code](https://claude.ai/code)

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

app/teams/page.tsx

@@ -41,9 +41,7 @@ export default function Teams() {
     try {
       const res = await fetch('/api/teams');
       const data = await res.json();
-      // Handle both old and new API response formats
-      const teams = data.success ? data.data : data;
-      setTeams(teams);
+      setTeams(data.data);
     } catch (error) {
       console.error('Error fetching teams:', error);
     } finally {