feat(cli): add create command

packages/vant-cli/src/commands/create.ts

@@ -0,0 +1,15 @@
+import { GENERATOR_DIR, CWD } from '../common/constant';
+import { VantCliGenerator } from '../compiler/vant-cli-generator';
+
+export async function create() {
+  const generator = new VantCliGenerator([], {
+    env: {
+      cwd: CWD
+    },
+    resolved: GENERATOR_DIR
+  });
+
+  return new Promise(resolve => {
+    generator.run(resolve);
+  });
+}