REFACTOR(repo): simplify project structure

- Move services/nextjs to nextjs/
- Move deploy/docker/Dockerfile.prod to Dockerfile
- Add GitHub Actions workflows (ci.yml, build.yml)
- Remove deploy/, services/, scripts/ folders

nextjs/app/api/auth/logout/route.ts

@@ -0,0 +1,22 @@
+import { NextRequest, NextResponse } from 'next/server'
+
+export async function POST(req: NextRequest) {
+  try {
+    // Create response
+    const response = NextResponse.json({
+      message: 'Logout successful',
+    })
+
+    // Clear auth token cookie
+    response.cookies.delete('auth-token')
+
+    return response
+  } catch (error) {
+    console.error('Logout error:', error)
+    return NextResponse.json(
+      { error: 'Internal server error' },
+      { status: 500 }
+    )
+  }
+}
+