feat(HAI-071): add Bun single-binary compile support for CLI

- Create build script (packages/cli/build.ts) using Bun.build compile target
- Update asset resolution in dashboard server for bundled context
- Add npm scripts to wire up the build process
- Add build-exe tests to verify compiled binary output
- Fix pre-existing build errors in engine and core packages
- Document build and compile workflow in README

packages/cli/package.json

@@ -8,6 +8,7 @@
   "scripts": {
     "dev": "tsx src/bin.ts",
     "build": "tsc",
+    "build:exe": "bun run build.ts",
     "typecheck": "tsc --noEmit",
     "test": "vitest run"
   },