Adds in AI chatting system.

prisma/schema.prisma

@@ -123,3 +123,25 @@ model Authenticator {
 
   @@map("authenticators")
 }
+
+// --- Add Chat Models ---
+
+model ChatThread {
+  id        String        @id @default(uuid())
+  createdAt DateTime      @default(now()) @map("created_at")
+  updatedAt DateTime      @updatedAt @map("updated_at")
+  messages  ChatMessage[]
+
+  @@map("chat_threads")
+}
+
+model ChatMessage {
+  id        String     @id @default(uuid())
+  threadId  String     @map("thread_id")
+  sender    String // 'user' or 'bot'
+  content   String
+  createdAt DateTime   @default(now()) @map("created_at")
+  thread    ChatThread @relation(fields: [threadId], references: [id], onDelete: Cascade)
+
+  @@map("chat_messages")
+}