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/edit/[id]/page.tsx

@@ -65,8 +65,7 @@ export default function EditStream() {
           team_id: streamData.team_id,
         });
         
-        // Handle both old and new API response formats
-        const teams = teamsData.success ? teamsData.data : teamsData;
+        const teams = teamsData.data;
         
         // Map teams for dropdown
         setTeams(