feat: setup database-driven admin user management

prisma/schema.prisma

@@ -83,3 +83,12 @@ model AboutSection {
   badgeIkoLabel   String
   updatedAt       DateTime @updatedAt
 }
+
+model User {
+  id        Int      @id @default(autoincrement())
+  username  String   @unique
+  password  String
+  createdAt DateTime @default(now())
+  updatedAt DateTime @updatedAt
+}
+