Greptile Summary

This PR improves cross-platform compatibility by replacing the bash-only bundle-a2ui.sh script with a cross-platform TypeScript equivalent (bundle-a2ui.mts) and updating the package.json invocation accordingly. Previously flagged issues (Chinese comments, missing error handler, mixed path separators, retained shell script) have all been addressed in this version.

Key changes:

• package.json: canvas:a2ui:bundle now uses node --import tsx scripts/bundle-a2ui.mts instead of bash scripts/bundle-a2ui.sh, enabling native Windows support.
• scripts/bundle-a2ui.mts: New TypeScript script that re-implements all bash logic (directory existence checks, SHA-256 hash-based cache invalidation, tsc compilation, rolldown bundling) using Node.js built-ins and pnpm exec/pnpm dlx for binary resolution.
• scripts/bundle-a2ui.sh: Correctly deleted as dead code.
• .github/workflows/ci.yml: Incidental indentation fix to the Python heredoc in the zizmor audit step — the new indentation correctly aligns the PY terminator at column 0 after YAML block-scalar processing, which is required for <<'PY' heredoc termination in bash.

Remaining concern: The inner try/catch around pnpm -s exec rolldown (lines 78–82) catches all non-zero exits, including genuine rolldown build errors (bad config, missing source file, etc.). This causes an unnecessary pnpm dlx rolldown download before the real error is surfaced, producing confusing duplicate error output. Checking for the binary's existence before choosing the invocation path would be cleaner and more deterministic.

Confidence Score: 3/5

• Safe to merge with one logic concern in the rolldown error handling that may produce confusing output on build failures.
• The core goal (replacing bash with Node.js for Windows compatibility) is well-implemented and all previous review comments have been addressed. The main remaining issue is the overly broad catch block around pnpm -s exec rolldown, which silently swallows genuine rolldown build errors and triggers an unnecessary pnpm dlx re-download before the real error is surfaced. This is a developer-experience bug rather than a correctness or security issue, but it could cause meaningful confusion during development. The incidental CI YAML fix is a net positive.
• scripts/bundle-a2ui.mts lines 78–82 (rolldown error handling)

This is a comment left during a code review.
Path: scripts/bundle-a2ui.mts
Line: 78-82

Comment:
**Catch-all swallows genuine build errors from rolldown**

The inner `catch` at line 80 catches **any** non-zero exit from `pnpm -s exec rolldown`, not only "rolldown binary not found in local node_modules." This means:

1. If rolldown is installed locally but the bundler config or source files have an error (syntax mistake, missing import, etc.), the first `exec` throws.
2. The `catch` silently falls back to `pnpm -s dlx rolldown`, potentially re-downloading rolldown.
3. `pnpm dlx rolldown` runs with the **same broken config**, fails again, and the outer `catch` finally surfaces the error.

Users see two sets of rolldown error output and a misleading "downloading rolldown" phase, making it look like the failure is a missing binary rather than a build problem.

A safer pattern is to probe for the binary's existence first, then choose the invocation path, rather than relying on a broad catch:

```typescript
import { existsSync } from "node:fs";

const rolldownLocalBin = path.join(ROOT_DIR, "node_modules/.bin/rolldown");
const rolldownCmd = existsSync(rolldownLocalBin)
  ? `"${rolldownLocalBin}"`
  : `pnpm -s dlx rolldown`;

exec(`${rolldownCmd} -c "${path.join(A2UI_APP_DIR, "rolldown.config.mjs")}"`);
```

This way, rolldown build errors are always surfaced immediately without the confusing re-download detour.

How can I resolve this? If you propose a fix, please make it concise.

_{Last reviewed commit: 5dc8633}