feat: add plan2code-bot with --resume capability and state cleanup

Add the autonomous workflow test runner (plan2code-bot) that uses the
Claude Agent SDK to run plan2code end-to-end. Includes --resume flag
to continue incomplete runs from saved state, and automatic state file
cleanup on successful completion.

plan2code-bot/tsup.config.ts

@@ -0,0 +1,15 @@
+import { defineConfig } from 'tsup';
+
+export default defineConfig({
+  entry: {
+    'bin/plan2code-bot': 'src/bin/plan2code-bot.ts',
+    index: 'src/index.ts',
+  },
+  format: ['esm'],
+  dts: false,
+  clean: true,
+  sourcemap: true,
+  banner: {
+    js: '#!/usr/bin/env node',
+  },
+});