chore: migrate middleware.ts to proxy.ts (#1067)

Author: ken-matsui

middleware.ts proxy.tsmiddleware.ts renamed to proxy.ts

@@ -2,7 +2,7 @@ import { type NextRequest, NextResponse } from "next/server";
 
 const IS_DEV = process.env.NODE_ENV === "development";
 
-export function middleware(request: NextRequest) {
+export function proxy(request: NextRequest) {
     const nonce = Buffer.from(crypto.randomUUID()).toString("base64");
 
     // TODO: unsafe-inline is needed for NextUI?