fix: remove conflicting middleware.ts, proxy.ts already handles locale routing

Next.js 16 uses proxy.ts instead of middleware.ts. The existing proxy.ts
already includes next-intl locale routing + auth guards. CACHE_BUST=5.

Dockerfile

@@ -4,7 +4,7 @@ WORKDIR /app
 
 # --- Install + Build in one stage ---
 FROM base AS builder
-ARG CACHE_BUST=4
+ARG CACHE_BUST=5
 COPY . .
 RUN pnpm install --no-frozen-lockfile
 ENV NEXT_TELEMETRY_DISABLED=1

apps/web/middleware.ts

@@ -1,15 +0,0 @@
-import createMiddleware from 'next-intl/middleware';
-
-import { routing } from '@kit/i18n/routing';
-
-export default createMiddleware(routing);
-
-export const config = {
-  matcher: [
-    // Match all pathnames except:
-    // - API routes (/api/...)
-    // - Next.js internals (/_next/...)
-    // - Static files with extensions
-    '/((?!api|_next|.*\\..*).*)',
-  ],
-};