feat: migrate payment provider to easy-pay, add order history and refund support

- Replace zpay with easy-pay payment provider (new lib/easy-pay/ module)
- Add order history page for users (pay/orders)
- Add GET /api/orders/my endpoint to list user's own orders
- Add GET /api/users/[id] endpoint for sub2api user lookup
- Add order status tracking module (lib/order/status.ts)
- Update config to support easy-pay credentials (merchant ID, key, gateway)
- Update PaymentForm and PaymentQRCode components for easy-pay flow
- Update pay page and admin page with new order management UI
- Update order service to support easy-pay, cancellation, and refund

package.json

@@ -0,0 +1,43 @@
+{
+  "name": "sub2apipay",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "dev": "next dev",
+    "build": "next build",
+    "start": "next start",
+    "lint": "eslint",
+    "test": "vitest run",
+    "test:watch": "vitest"
+  },
+  "dependencies": {
+    "@prisma/adapter-pg": "7.4.1",
+    "@prisma/client": "^7.4.2",
+    "next": "16.1.6",
+    "pg": "^8.19.0",
+    "react": "19.2.3",
+    "react-dom": "19.2.3",
+    "zod": "^4.3.6"
+  },
+  "pnpm": {
+    "onlyBuiltDependencies": [
+      "prisma",
+      "@prisma/engines",
+      "esbuild"
+    ]
+  },
+  "devDependencies": {
+    "@tailwindcss/postcss": "^4",
+    "@types/node": "^20",
+    "@types/pg": "^8.16.0",
+    "@types/react": "^19",
+    "@types/react-dom": "^19",
+    "@vitejs/plugin-react": "^5.1.4",
+    "eslint": "^9",
+    "eslint-config-next": "16.1.6",
+    "prisma": "7.4.1",
+    "tailwindcss": "^4",
+    "typescript": "^5",
+    "vitest": "^4.0.18"
+  }
+}