feat(compiler-core): support mode: cjs in codegen

packages/compiler-core/src/options.ts

@@ -57,8 +57,10 @@ export interface CodegenOptions {
   // - Function mode will generate a single `const { helpers... } = Vue`
   //   statement and return the render function. It is meant to be used with
   //   `new Function(code)()` to generate a render function at runtime.
+  // - CommonJS mode is like function mode except it retrives helpers from
+  //   `require('vue')`.
   // - Default: 'function'
-  mode?: 'module' | 'function'
+  mode?: 'module' | 'function' | 'cjs'
   // Prefix suitable identifiers with _ctx.
   // If this option is false, the generated code will be wrapped in a
   // `with (this) { ... }` block.