Fix backup directory detection in CI tests

- Change backup detection to use startsWith('.claude.backup-') for exact match
- This should fix the backup test that was failing to find backup directories

Author: Matt-Dionis

claude-config-composer/tests/integration/cli.test.ts

@@ -140,7 +140,7 @@ describe('CLI Integration Tests', () => {
 
       // Check that backup was created
       const files = await fs.readdir(testDir);
-      const backupDir = files.find(f => f.includes('.backup-'));
+      const backupDir = files.find(f => f.startsWith('.claude.backup-'));
       expect(backupDir).toBeDefined();
 
       if (backupDir) {