fix: address second PR review — clean replace, IDE failure bubbling, bun validation

- cpSync now does rmSync before copy to avoid stale file merges
- setupIDEs() returns failed IDE list; install reports partial success
- runSmartInstall() returns boolean status instead of void
- Worker port in next-steps URL reads CLAUDE_MEM_WORKER_PORT env var
- Goose YAML regex stops at column-0 keys (prevents eating sibling sections)
- AGENTS.md uninstall removes header-only stub files
- findBunPath() validated before use in WindsurfHooksInstaller
- Cursor marked unsupported in ide-detection until installer is wired

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

tests/install-non-tty.test.ts

@@ -91,7 +91,7 @@ describe('Install Non-TTY Support', () => {
     });
 
     it('uses console.log for note/summary in non-interactive mode', () => {
-      expect(installSource).toContain("console.log('\\n  Installation Complete')");
+      expect(installSource).toContain("console.log(`\\n  ${installStatus}`)");
     });
   });