fix(mf): __webpack_init_sharing__ with empty config (#6450)

packages/rspack-test-tools/tests/configCases/container-1-0/init-sharing-without-config/index.js

@@ -0,0 +1,4 @@
+it("should have single runtime chunk", () => {
+	__webpack_init_sharing__("default");
+	expect(typeof __webpack_require__.I).toBe("function")
+});

packages/rspack-test-tools/tests/configCases/container-1-0/init-sharing-without-config/webpack.config.js

@@ -0,0 +1,8 @@
+const { ModuleFederationPluginV1: ModuleFederationPlugin } = require("@rspack/core").container;
+
+/** @type {import("@rspack/core").Configuration} */
+module.exports = {
+	plugins: [
+		new ModuleFederationPlugin({}),
+	]
+};

packages/rspack/src/container/ModuleFederationPluginV1.ts

@@ -9,6 +9,7 @@ import { SharePlugin, Shared } from "../sharing/SharePlugin";
 import { isValidate } from "../util/validate";
 import { ContainerPlugin, Exposes } from "./ContainerPlugin";
 import { ContainerReferencePlugin, Remotes } from "./ContainerReferencePlugin";
+import { ShareRuntimePlugin } from "../sharing/ShareRuntimePlugin";
 
 export interface ModuleFederationPluginV1Options {
 	exposes?: Exposes;
@@ -43,6 +44,7 @@ export class ModuleFederationPluginV1 {
 			compiler.options.output.enabledLibraryTypes!.push(library.type);
 		}
 		compiler.hooks.afterPlugins.tap("ModuleFederationPlugin", () => {
+			new ShareRuntimePlugin(this._options.enhanced).apply(compiler);
 			if (
 				options.exposes &&
 				(Array.isArray(options.exposes)