The VS Code extension no longer implements any business logic — every
capability (module discovery, path resolution, system info, builds,
tests, clean) lives in Tito CLI commands. The extension is a pure UI
shell that delegates via `python3 -m tito.main`.
Tito CLI additions:
- `module list --json` for machine-readable module discovery
- `module path <num> --notebook|--source|--about` for file resolution
- `system info --json` for environment info
- `dev build html|serve|pdf|paper` wrapping make targets
- `dev clean [all|site]` wrapping make clean
- Banner suppression for --json and module path output
Extension hardening:
- Centralized CLI integration in utils/tito.ts (single TITO_CMD constant,
callTito, callTitoJson, titoTerminalCommand, isTitoAvailable, log/logError)
- Replaced all silent catch{} blocks with logged errors and user feedback
- Module tree shows error/empty states with actionable Setup/Health buttons
- Info tree shows "Tito CLI unavailable" when CLI is unreachable
- Removed all setTimeout refresh hacks — file watcher on .tito/progress.json
is the sole refresh mechanism
- Exit code tracking via onDidEndTerminalShellExecution
- Tito availability pre-flight check on activation
- BUILD_OUTPUTS constants for build artifact paths
- Zero execSync calls outside tito.ts, zero hardcoded command strings
