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>

src/npx-cli/commands/ide-detection.ts

@@ -116,7 +116,7 @@ export function detectInstalledIDEs(): IDEInfo[] {
       id: 'cursor',
       label: 'Cursor',
       detected: existsSync(join(home, '.cursor')),
-      supported: true,
+      supported: false,
     },
     {
       id: 'copilot-cli',