feat: add admin authentication and management features

- Implemented Prisma schema with models for AdminUser, AppSettings, and Snapshot.
- Created seed script to initialize the database with an admin user and JWT secret.
- Developed admin login page with form handling and error management.
- Added API routes for admin login, logout, change password, and JWT verification.
- Integrated Stripe for payment intent management in admin orders.
- Established middleware for protecting admin routes with JWT authentication.
- Created Zustand stores for managing persona and snapshot states.

prisma/schema.prisma

@@ -0,0 +1,28 @@
+generator client {
+  provider = "prisma-client"
+  output   = "../src/generated/prisma"
+}
+
+datasource db {
+  provider = "sqlite"
+}
+
+model AdminUser {
+  id           String   @id @default(cuid())
+  username     String   @unique
+  passwordHash String
+  createdAt    DateTime @default(now())
+  updatedAt    DateTime @updatedAt
+}
+
+model AppSettings {
+  key       String   @id
+  value     String
+  updatedAt DateTime @updatedAt
+}
+
+model Snapshot {
+  paymentIntentId String   @id
+  imageData       String
+  createdAt       DateTime @default(now())
+}

prisma/seed.ts

@@ -0,0 +1,60 @@
+import { PrismaClient } from '../src/generated/prisma/client.js';
+import { PrismaLibSql } from '@prisma/adapter-libsql';
+import bcrypt from 'bcryptjs';
+import { randomBytes } from 'crypto';
+import path from 'path';
+
+const dbPath = path.resolve(process.cwd(), 'prisma', 'lootah.db');
+const adapter = new PrismaLibSql({ url: `file:${dbPath}` });
+const prisma = new PrismaClient({ adapter } as ConstructorParameters<typeof PrismaClient>[0]);
+
+async function main() {
+  console.log('Seeding database...');
+
+  // Create default admin user
+  const existingAdmin = await prisma.adminUser.findUnique({
+    where: { username: 'admin' },
+  });
+
+  if (!existingAdmin) {
+    const passwordHash = await bcrypt.hash('admin123', 12);
+    await prisma.adminUser.create({
+      data: {
+        username: 'admin',
+        passwordHash,
+      },
+    });
+    console.log('✓ Created admin user (username: admin, password: admin123)');
+    console.log('  ⚠️  Change the password after first login!');
+  } else {
+    console.log('✓ Admin user already exists, skipping.');
+  }
+
+  // Generate and store JWT secret
+  const existingSecret = await prisma.appSettings.findUnique({
+    where: { key: 'jwt_secret' },
+  });
+
+  if (!existingSecret) {
+    const jwtSecret = randomBytes(64).toString('hex');
+    await prisma.appSettings.upsert({
+      where: { key: 'jwt_secret' },
+      update: { value: jwtSecret },
+      create: { key: 'jwt_secret', value: jwtSecret },
+    });
+    console.log('✓ Generated JWT secret and stored in database.');
+  } else {
+    console.log('✓ JWT secret already exists, skipping.');
+  }
+
+  console.log('Seeding complete!');
+}
+
+main()
+  .catch((e) => {
+    console.error(e);
+    process.exit(1);
+  })
+  .finally(async () => {
+    await prisma.$disconnect();
+  });