Fix: use yarn dlx for remote package execution in Yarn2Proxy

When `useRemotePkg` is true, `Yarn2Proxy.runPackageCommand` now uses
`yarn dlx` instead of `yarn exec`. `yarn exec` only runs locally
installed binaries, causing exit code 127 when attempting to download
and run a remote package (e.g. `storybook@10.2.7`) during addon
postinstall on Yarn 2+.

Fixes #33844

Author: Your Name

code/core/src/common/js-package-manager/Yarn2Proxy.test.ts

@@ -67,6 +67,24 @@ describe('Yarn 2 Proxy', () => {
         })
       );
     });
+
+    it('should use `yarn dlx` when useRemotePkg is true', async () => {
+      const executeCommandSpy = mockedExecuteCommand.mockResolvedValue({
+        stdout: '',
+      } as any);
+
+      await yarn2Proxy.runPackageCommand({
+        args: ['storybook@latest', 'automigrate'],
+        useRemotePkg: true,
+      });
+
+      expect(executeCommandSpy).toHaveBeenLastCalledWith(
+        expect.objectContaining({
+          command: 'yarn',
+          args: ['dlx', 'storybook@latest', 'automigrate'],
+        })
+      );
+    });
   });
 
   describe('addDependencies', () => {

code/core/src/common/js-package-manager/Yarn2Proxy.ts

@@ -100,11 +100,15 @@ export class Yarn2Proxy extends JsPackageManager {
 
   public runPackageCommand({
     args,
+    useRemotePkg = false,
     ...options
-  }: Omit<ExecuteCommandOptions, 'command'> & { args: string[] }): ResultPromise {
+  }: Omit<ExecuteCommandOptions, 'command'> & {
+    args: string[];
+    useRemotePkg?: boolean;
+  }): ResultPromise {
     return executeCommand({
       command: 'yarn',
-      args: ['exec', ...args],
+      args: [useRemotePkg ? 'dlx' : 'exec', ...args],
       ...options,
     });
   }