Fix Next.js 15 compatibility and TypeScript errors

- Update API route handlers to use async params for Next.js 15 compatibility
- Fix MUI DataGrid deprecated props (pageSize -> initialState.pagination)
- Replace Material-UI Grid components with Box for better compatibility
- Fix admin authentication system with proper request parameters
- Update permission constants to match available AdminPermission enum values
- Add missing properties to Page interface for type safety
- Update .gitignore to exclude venv/, import logs, and large data directories
- Optimize Next.js config to reduce memory usage during builds

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/api/admin/pages/[id]/route.ts

@@ -4,7 +4,7 @@ import { verifyAdminAuth } from '@/lib/admin-auth';
 
 export async function GET(
   request: NextRequest,
-  { params }: { params: { id: string } }
+  { params }: { params: Promise<{ id: string }> }
 ) {
   try {
     const adminUser = await verifyAdminAuth(request);
@@ -12,8 +12,9 @@ export async function GET(
       return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
     }
 
+    const resolvedParams = await params;
     const page = await prisma.page.findUnique({
-      where: { id: params.id },
+      where: { id: resolvedParams.id },
       include: {
         creator: { select: { name: true, email: true } },
         updater: { select: { name: true, email: true } }
@@ -42,7 +43,7 @@ export async function GET(
 
 export async function PUT(
   request: NextRequest,
-  { params }: { params: { id: string } }
+  { params }: { params: Promise<{ id: string }> }
 ) {
   try {
     const adminUser = await verifyAdminAuth(request);
@@ -50,6 +51,7 @@ export async function PUT(
       return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
     }
 
+    const resolvedParams = await params;
     const body = await request.json();
     const {
       title,
@@ -69,7 +71,7 @@ export async function PUT(
 
     // Check if page exists
     const existingPage = await prisma.page.findUnique({
-      where: { id: params.id }
+      where: { id: resolvedParams.id }
     });
 
     if (!existingPage) {
@@ -85,7 +87,7 @@ export async function PUT(
         where: { slug }
       });
 
-      if (conflictingPage && conflictingPage.id !== params.id) {
+      if (conflictingPage && conflictingPage.id !== resolvedParams.id) {
         return NextResponse.json(
           { success: false, error: 'A page with this slug already exists' },
           { status: 400 }
@@ -94,7 +96,7 @@ export async function PUT(
     }
 
     const updatedPage = await prisma.page.update({
-      where: { id: params.id },
+      where: { id: resolvedParams.id },
       data: {
         title,
         slug,
@@ -137,7 +139,7 @@ export async function PUT(
 
 export async function DELETE(
   request: NextRequest,
-  { params }: { params: { id: string } }
+  { params }: { params: Promise<{ id: string }> }
 ) {
   try {
     const adminUser = await verifyAdminAuth(request);
@@ -145,8 +147,9 @@ export async function DELETE(
       return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
     }
 
+    const resolvedParams = await params;
     const page = await prisma.page.findUnique({
-      where: { id: params.id }
+      where: { id: resolvedParams.id }
     });
 
     if (!page) {
@@ -157,7 +160,7 @@ export async function DELETE(
     }
 
     await prisma.page.delete({
-      where: { id: params.id }
+      where: { id: resolvedParams.id }
     });
 
     return NextResponse.json({