[Enhancement] Add installation summary table at the end

```
After all tools are installed, print a summary table:

  Tool          Status       Version
  ──────────────────────────────────
  git           ✅ Installed  2.43.0
  nodejs        ✅ Installed  20.11.0
  docker        ❌ Failed     —
  vscode        ✅ Installed  1.85.0

This gives developers a clear record of what happened.

File to edit: index.js
```