refactor: Move Next.js proxy module into server directory

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: brkalow

packages/nextjs/src/server/index.ts

@@ -81,7 +81,8 @@ export { reverificationErrorResponse, reverificationError } from '@clerk/backend
 export {
   clerkFrontendApiProxy,
   createFrontendApiProxyHandlers,
+  DEFAULT_PROXY_PATH,
   type FrontendApiProxyHandlers,
+  type FrontendApiProxyOptions,
   type NextFrontendApiProxyOptions,
-} from '../proxy';
-export { DEFAULT_PROXY_PATH, type FrontendApiProxyOptions } from '@clerk/backend/proxy';
+} from './proxy';

packages/nextjs/src/proxy.ts packages/nextjs/src/server/proxy.tspackages/nextjs/src/proxy.ts renamed to packages/nextjs/src/server/proxy.ts

@@ -4,7 +4,7 @@ import {
   type FrontendApiProxyOptions,
 } from '@clerk/backend/proxy';
 
-import { PUBLISHABLE_KEY, SECRET_KEY } from './server/constants';
+import { PUBLISHABLE_KEY, SECRET_KEY } from './constants';
 
 export { DEFAULT_PROXY_PATH, type FrontendApiProxyOptions } from '@clerk/backend/proxy';