Build: stop tracking bundled artifacts (#2455) (thanks @0oAstro)

Co-authored-by: 0oAstro <0oAstro@users.noreply.github.com>

docs/start/getting-started.md

@@ -175,6 +175,7 @@ clawdbot onboard --install-daemon
 ```
 
 If you don’t have a global install yet, run the onboarding step via `pnpm clawdbot ...` from the repo.
+`pnpm build` also bundles A2UI assets; if you need to run just that step, use `pnpm canvas:a2ui:bundle`.
 
 Gateway (from this repo):