refactor: migrate a2ui bundle script to typescript

Replace the bash-based bundling script with a TypeScript implementation
to improve cross-platform compatibility and maintainability. The new
script includes logic for change detection via file hashing to skip
unnecessary rebuilds.

package.json

@@ -143,7 +143,7 @@
     "protocol:gen": "node --import tsx scripts/protocol-gen.ts",
     "protocol:gen:swift": "node --import tsx scripts/protocol-gen-swift.ts",
     "protocol:check": "pnpm protocol:gen && pnpm protocol:gen:swift && git diff --exit-code -- dist/protocol.schema.json apps/macos/Sources/MoltbotProtocol/GatewayModels.swift",
-    "canvas:a2ui:bundle": "bash scripts/bundle-a2ui.sh",
+    "canvas:a2ui:bundle": "node --import tsx scripts/bundle-a2ui.ts",
     "check:loc": "node --import tsx scripts/check-ts-max-loc.ts --max 500"
   },
   "keywords": [],

scripts/bundle-a2ui.ts

@@ -0,0 +1,119 @@
+import { createHash } from "node:crypto";
+import { promises as fs } from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import { execSync } from "node:child_process";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const ROOT_DIR = path.resolve(__dirname, "..");
+
+const HASH_FILE = path.join(ROOT_DIR, "src/canvas-host/a2ui/.bundle.hash");
+const OUTPUT_FILE = path.join(ROOT_DIR, "src/canvas-host/a2ui/a2ui.bundle.js");
+const A2UI_RENDERER_DIR = path.join(ROOT_DIR, "vendor/a2ui/renderers/lit");
+const A2UI_APP_DIR = path.join(ROOT_DIR, "apps/shared/MoltbotKit/Tools/CanvasA2UI");
+
+async function exists(p: string) {
+  try {
+    await fs.access(p);
+    return true;
+  } catch {
+    return false;
+  }
+}
+
+async function main() {
+  if (!(await exists(A2UI_RENDERER_DIR)) || !(await exists(A2UI_APP_DIR))) {
+    console.log("A2UI sources missing; keeping prebuilt bundle.");
+    process.exit(0);
+  }
+
+  const INPUT_PATHS = [
+    path.join(ROOT_DIR, "package.json"),
+    path.join(ROOT_DIR, "pnpm-lock.yaml"),
+    A2UI_RENDERER_DIR,
+    A2UI_APP_DIR,
+  ];
+
+  const currentHash = await computeHash(INPUT_PATHS);
+
+  let skip = false;
+  if (await exists(HASH_FILE)) {
+    const previousHash = (await fs.readFile(HASH_FILE, "utf8")).trim();
+    if (previousHash === currentHash && (await exists(OUTPUT_FILE))) {
+      console.log("A2UI bundle up to date; skipping.");
+      skip = true;
+    }
+  }
+
+  if (!skip) {
+    try {
+      // We use `npx` or local `node_modules/.bin` executables.
+      // Since we are running with pnpm, `tsc` and `rolldown` should be in path if run via pnpm exec or similar.
+      // The bash script used `pnpm -s exec tsc`.
+      
+      console.log("Running tsc...");
+      execSync(`pnpm -s exec tsc -p "${path.join(A2UI_RENDERER_DIR, "tsconfig.json")}"`, {
+        stdio: "inherit",
+        cwd: ROOT_DIR
+      });
+
+      console.log("Running rolldown...");
+      // rolldown might need to be run via pnpm exec or npx if not in path
+      execSync(`pnpm exec rolldown -c "${path.join(A2UI_APP_DIR, "rolldown.config.mjs")}"`, {
+        stdio: "inherit",
+        cwd: ROOT_DIR
+      });
+
+      await fs.writeFile(HASH_FILE, currentHash);
+    } catch (e) {
+      console.error("A2UI bundling failed. Re-run with: pnpm canvas:a2ui:bundle");
+      console.error("If this persists, verify pnpm deps and try again.");
+      process.exit(1);
+    }
+  }
+}
+
+async function computeHash(inputs: string[]) {
+  const files: string[] = [];
+
+  async function walk(entryPath: string) {
+    const st = await fs.stat(entryPath);
+    if (st.isDirectory()) {
+      const entries = await fs.readdir(entryPath);
+      for (const entry of entries) {
+        await walk(path.join(entryPath, entry));
+      }
+    } else {
+      files.push(entryPath);
+    }
+  }
+
+  for (const input of inputs) {
+    await walk(input);
+  }
+
+  // Normalize paths for consistent sorting
+  files.sort((a, b) => normalize(a).localeCompare(normalize(b)));
+
+  const hash = createHash("sha256");
+  for (const filePath of files) {
+    const rel = normalize(path.relative(ROOT_DIR, filePath));
+    hash.update(rel);
+    hash.update("\0");
+    const content = await fs.readFile(filePath);
+    hash.update(content);
+    hash.update("\0");
+  }
+
+  return hash.digest("hex");
+}
+
+function normalize(p: string) {
+  return p.split(path.sep).join("/");
+}
+
+main().catch((e) => {
+  console.error(e);
+  process.exit(1);
+});