feat(purchase): 新增 Apple 内购完整链路

- AppleReceiptController 改造：验签后立刻落库并解锁权益
- 新增 ApplePurchaseService 处理业务：防重、写订单、发道具
- 新增 KeyboardUserPurchaseRecords 实体与 Mapper，记录用户购买
- ErrorCode 补充 RECEIPT_INVALID(50016)
- 删除过期 AGENTS.md，修正 i18n_message 表名与 CORS 白名单

src/main/java/com/yolo/keyborad/controller/AppleReceiptController.java

@@ -1,6 +1,12 @@
 package com.yolo.keyborad.controller;
 
+import cn.dev33.satoken.stp.StpUtil;
+import com.yolo.keyborad.common.BaseResponse;
+import com.yolo.keyborad.common.ErrorCode;
+import com.yolo.keyborad.common.ResultUtils;
+import com.yolo.keyborad.exception.BusinessException;
 import com.yolo.keyborad.model.dto.AppleReceiptValidationResult;
+import com.yolo.keyborad.service.ApplePurchaseService;
 import com.yolo.keyborad.service.AppleReceiptService;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestBody;
@@ -14,14 +20,32 @@ import java.util.Map;
 public class AppleReceiptController {
 
     private final AppleReceiptService appleReceiptService;
+    private final ApplePurchaseService applePurchaseService;
 
-    public AppleReceiptController(AppleReceiptService appleReceiptService) {
+    public AppleReceiptController(AppleReceiptService appleReceiptService,
+                                  ApplePurchaseService applePurchaseService) {
         this.appleReceiptService = appleReceiptService;
+        this.applePurchaseService = applePurchaseService;
     }
 
+//    @PostMapping("/validate-receipt")
+//    public AppleReceiptValidationResult validateReceipt(@RequestBody Map<String, String> body) {
+//        String receipt = body.get("receipt");
+//        return appleReceiptService.validateReceipt(receipt);
+//    }
+
     @PostMapping("/validate-receipt")
-    public AppleReceiptValidationResult validateReceipt(@RequestBody Map<String, String> body) {
+    public BaseResponse<Boolean> handlePurchase(@RequestBody Map<String, String> body) {
         String receipt = body.get("receipt");
-        return appleReceiptService.validateReceipt(receipt);
+        if (receipt == null || receipt.isBlank()) {
+            throw new BusinessException(ErrorCode.PARAMS_ERROR, "receipt 不能为空");
+        }
+        Long userId = StpUtil.getLoginIdAsLong();
+        AppleReceiptValidationResult validationResult = appleReceiptService.validateReceipt(receipt);
+        applePurchaseService.processPurchase(userId, validationResult);
+        return ResultUtils.success(Boolean.TRUE);
     }
+
+
+
 }