Fix React 19 server bundle errors by removing 'use client' from .server.tsx files

Files ending with .server.tsx are intended for server-side rendering and should
not have the 'use client' directive. This directive causes webpack to bundle
these files as client components, which leads to errors when React 19's server
exports don't include client-only APIs like createContext, useContext, and
Component.

This fixes CI errors:
- export 'createContext' was not found in 'react'
- export 'useContext' was not found in 'react'
- export 'Component' was not found in 'react'

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: justin808

react_on_rails_pro/spec/dummy/client/app/ror-auto-load-components/AsyncOnServerSyncOnClient.server.tsx

@@ -1,5 +1,3 @@
-'use client';
-
 import wrapServerComponentRenderer from 'react-on-rails-pro/wrapServerComponentRenderer/server';
 import AsyncOnServerSyncOnClient from '../components/AsyncOnServerSyncOnClient';
 

react_on_rails_pro/spec/dummy/client/app/ror-auto-load-components/LazyApolloGraphQLApp.server.tsx

@@ -1,5 +1,3 @@
-'use client';
-
 import React from 'react';
 import { renderToString } from 'react-dom/server';
 import { getMarkupFromTree } from '@apollo/client/react/ssr';

react_on_rails_pro/spec/dummy/client/app/ror-auto-load-components/ServerComponentRouter.server.tsx

@@ -1,5 +1,3 @@
-'use client';
-
 import * as React from 'react';
 import { StaticRouter } from 'react-router-dom/server.js';
 import { RailsContext, ReactComponentOrRenderFunction } from 'react-on-rails-pro';