feat: integrate unified payment and wallet refunds

backend/api/etc/heqi_dev.yaml

@@ -0,0 +1,49 @@
+Service: heqi
+Port: 12426
+
+Databases:
+  Driver: postgres
+  Source:
+    - host=8.137.107.29 user=postgres password=Weidong2023~! dbname=heqiapp_dev port=19432 sslmode=disable TimeZone=Asia/Shanghai
+
+# Redis 仅用于缓存、会话、限流和 Streams；首期外部事件适配使用 Mock。
+Cache: redis://default:Weidong2023~!@139.224.247.176:19379/1
+OnMicroService: false
+SecretKey: change-me-to-a-random-string
+
+Global:
+  UserRegisterURL: http://localhost:5174/register
+  ManualRechargeMaxAmount: 100000000
+  MockVerificationEnabled: true
+  MockVerificationCode: "123456"
+  VerificationTTLSeconds: 300
+  VerificationSendIntervalSeconds: 60
+  MockPaymentEnabled: true
+  DeliveryArrivalRadiusMeters: 200
+  UploadVideoMaxSize: 104857600
+  FieldEncryptionKey: change-me-32-byte-development-key
+
+Payment:
+  ExpireMinutes: 30
+  RefundWindowDays: 3
+  InternalServiceToken: change-me-payment-worker-token
+  Alipay:
+    Enabled: false
+    Production: false
+    AppID: ""
+    PrivateKeyPath: ""
+    AppPublicCertPath: ""
+    AlipayPublicCertPath: ""
+    AlipayRootCertPath: ""
+    NotifyURL: "https://example.invalid/heqi/payment-return/v1/alipay/notify"
+    ReturnURL: "https://example.invalid/payment/result"
+  Wechat:
+    Enabled: false
+    MerchantID: ""
+    MerchantCertificateSerial: ""
+    MerchantPrivateKeyPath: ""
+    APIv3Key: ""
+    AppAppID: ""
+    OfficialAccountAppID: ""
+    MiniProgramAppID: ""
+    NotifyURL: "https://example.invalid/heqi/payment-return/v1/wechat/notify"