feat: modernize with Next.js 16 standalone output, remove redundant babel compiler, update postcss

- Remove babel-plugin-react-compiler (Next.js 16 has built-in reactCompiler)
- Update postcss to 8.5.25
- Add output: 'standalone' to next.config.ts for smaller/faster deployments
- Update ecosystem.config.cjs to use standalone server.js

ecosystem.config.cjs

@@ -2,8 +2,7 @@ module.exports = {
   apps: [
     {
       name: "next",
-      script: "pnpm",
+      script: ".next/standalone/server.js",
-      args: "start",
       exec_mode: "cluster",
       instances: 0,
       max_memory_restart: "512M",

next.config.ts

@@ -34,13 +34,15 @@ const nextConfig: NextConfig = {
 	// Enable React Compiler for automatic memoization
 	reactCompiler: true,
 
-	// Compress responses with gzip
+	// Compress responses with gzip/brotli
 	compress: true,
 
-	// Disable Next.js telemetry
+	// Disable Next.js telemetry and browser sourcemaps in production
 	productionBrowserSourceMaps: false,
 
-	// Enable TypeScript CLI integration for TypeScript 7 compatibility
+	// Standalone output for smaller, faster Docker deployments and cold starts
+	output: "standalone",
+
 	experimental: {
 		useTypeScriptCli: true,
 	},