refactor(types): enforce platform nextConfig via type-only constraints

Assisted-by: Codex 5.3

Author: cursoragent

apps/site/next.config.mjs

@@ -21,16 +21,6 @@ const { default: platform } = DEPLOY_TARGET
   ? await import(`@node-core/platform-${DEPLOY_TARGET}/next.platform.config`)
   : await import('./next.platform.config.mjs');
 
-/**
- * Apply only an explicit allowlist of Next.js config keys from platform
- * packages so critical core config (e.g. `webpack`, `turbopack`) cannot be
- * overridden accidentally.
- */
-const platformNextConfigOverrides = {
-  env: platform.nextConfig?.env,
-  deploymentId: platform.nextConfig?.deploymentId,
-};
-
 /** @type {import('next').NextConfig} */
 const nextConfig = {
   // Full Support of React 18 SSR and Streaming
@@ -106,7 +96,7 @@ const nextConfig = {
     ...config,
     resolve: { ...resolve, alias: { ...resolve.alias, ...platform.aliases } },
   }),
-  ...platformNextConfigOverrides,
+  ...platform.nextConfig,
 };
 
 const withNextIntl = createNextIntlPlugin('./i18n.tsx');

packages/platform-cloudflare/next.platform.config.d.ts

@@ -1,14 +1,10 @@
 import type { NextConfig } from 'next';
 
-type PlatformMdxConfig = {
-  wasm?: boolean;
-  twoslash?: boolean;
-};
-
-type PlatformNextConfig = {
-  deploymentId?: string;
-  env?: NextConfig['env'];
-};
+type PlatformMdxConfig = Pick<
+  import('@node-core/rehype-shiki').HighlighterOptions,
+  'wasm' | 'twoslash'
+>;
+type PlatformNextConfig = Pick<NextConfig, 'deploymentId' | 'env'>;
 
 export type PlatformConfig = {
   aliases?: Record<string, string>;

packages/platform-vercel/next.platform.config.d.ts

@@ -1,14 +1,11 @@
 import type { NextConfig } from 'next';
 
-type PlatformMdxConfig = {
-  wasm?: boolean;
-  twoslash?: boolean;
-};
+type PlatformMdxConfig = Pick<
+  import('@node-core/rehype-shiki').HighlighterOptions,
+  'wasm' | 'twoslash'
+>;
 
-type PlatformNextConfig = {
-  deploymentId?: string;
-  env?: NextConfig['env'];
-};
+type PlatformNextConfig = Pick<NextConfig, 'deploymentId' | 'env'>;
 
 export type PlatformConfig = {
   aliases?: Record<string, string>;