feat: Implement contact message functionality including API endpoints, database storage, and email notifications.

prisma/schema.prisma

@@ -135,3 +135,12 @@ model File {
 
   @@index([folder, originalName])
 }
+
+model ContactMessage {
+  id        String   @id @default(uuid())
+  name      String
+  email     String
+  subject   String?
+  message   String
+  createdAt DateTime @default(now())
+}