init: add source code from src.zip

src/commands/exit/index.ts

@@ -0,0 +1,12 @@
+import type { Command } from '../../commands.js'
+
+const exit = {
+  type: 'local-jsx',
+  name: 'exit',
+  aliases: ['quit'],
+  description: 'Exit the REPL',
+  immediate: true,
+  load: () => import('./exit.js'),
+} satisfies Command
+
+export default exit