feat: add review writing page and integrate Steam account linking

- Implemented WriteReviewPage for users to submit reviews with ratings and playtime.
- Created global CSS styles for consistent theming across the application.
- Established RootLayout for metadata and global styles.
- Developed LoginPage for user authentication with email/password and Steam login options.
- Built Home page to display game search results and recent reviews.
- Added LinkSteamPage for linking Steam accounts to user profiles.
- Created ProfilePage to manage user information and display their reviews.
- Developed GameCard and ReviewCard components for displaying games and reviews.
- Implemented Header component for navigation and user session management.
- Added Providers component to wrap the application with session context.
- Integrated NextAuth for user authentication with Steam and credentials.
- Set up Prisma client for database interactions.
- Created Steam API utility functions for fetching game and user data.
- Configured TypeScript settings for the project.

src/app/api/steam/unlink/route.ts

@@ -0,0 +1,22 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { auth } from '@/lib/auth'
+import { prisma } from '@/lib/db'
+
+export async function POST(request: NextRequest) {
+  const session = await auth()
+
+  if (!session?.user?.id) {
+    return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+  }
+
+  await prisma.user.update({
+    where: { id: session.user.id },
+    data: {
+      steamId: null,
+      steamPersonaname: null,
+      steamAvatar: null
+    }
+  })
+
+  return NextResponse.json({ success: true })
+}