修复：防止提现创建中的竞态条件和重复收益

- 在 earnings_line 表添加唯一约束 (tenant_id, order_id, clerk_id, earning_type, deleted)
- 重排提现创建流程：先预留收益行，成功后才创建提现请求
- 在收益行预留时添加状态验证，检测并发修改
- 使用临时提现ID进行预留，创建请求后替换为真实ID
- 添加唯一约束前先清理重复的收益记录（V10 迁移）

此修复解决了关键的竞态条件问题：并发提现可能创建没有资金支持的孤儿请求记录。
修复后确保快速失败行为 - 如果收益行已被占用，提现请求永远不会被创建。

play-admin/src/main/java/com/starry/admin/modules/withdraw/service/impl/WithdrawalServiceImpl.java

@@ -65,6 +65,23 @@ public class WithdrawalServiceImpl extends ServiceImpl<WithdrawalRequestMapper,
         List<EarningsLineEntity> lines = earningsService.findWithdrawable(clerkId, amount, now);
         if (lines.isEmpty()) throw new CustomException("可提现余额不足");
 
+        // Reserve lines FIRST with temp ID (fail fast before creating request)
+        String tempWithdrawalId = "TEMP_" + IdUtils.getUuid();
+        int reservedCount = 0;
+        for (EarningsLineEntity line : lines) {
+            boolean updated = earningsService.update(Wrappers.lambdaUpdate(EarningsLineEntity.class)
+                    .eq(EarningsLineEntity::getId, line.getId())
+                    .eq(EarningsLineEntity::getStatus, line.getStatus()) // Verify status unchanged
+                    .set(EarningsLineEntity::getStatus, "withdrawing")
+                    .set(EarningsLineEntity::getWithdrawalId, tempWithdrawalId));
+            if (!updated) {
+                // Another request already took this line
+                throw new CustomException("部分收益已被其他提现请求锁定，请重试");
+            }
+            reservedCount++;
+        }
+
+        // Only NOW create the request (after successful reservation)
         LocalDateTime confirmedAt = payeeProfile.getLastConfirmedAt();
         String snapshotJson = buildPayeeSnapshot(payeeProfile, confirmedAt);
 
@@ -80,20 +97,17 @@ public class WithdrawalServiceImpl extends ServiceImpl<WithdrawalRequestMapper,
         req.setStatus("pending");
         req.setOutBizNo(req.getId());
         this.save(req);
+
+        // Update temp ID to real ID
+        earningsService.update(Wrappers.lambdaUpdate(EarningsLineEntity.class)
+                .eq(EarningsLineEntity::getWithdrawalId, tempWithdrawalId)
+                .set(EarningsLineEntity::getWithdrawalId, req.getId()));
+
         // log created
         withdrawalLogService.log(req.getTenantId(), clerkId, req.getId(),
                 "CREATED", null, req.getStatus(), "提现申请创建", null);
         withdrawalLogService.log(req.getTenantId(), clerkId, req.getId(),
                 "PAYEE_CONFIRMED", req.getStatus(), req.getStatus(), "店员确认收款码", snapshotJson);
-
-        int reservedCount = 0;
-        for (EarningsLineEntity line : lines) {
-            earningsService.update(Wrappers.lambdaUpdate(EarningsLineEntity.class)
-                    .eq(EarningsLineEntity::getId, line.getId())
-                    .set(EarningsLineEntity::getStatus, "withdrawing")
-                    .set(EarningsLineEntity::getWithdrawalId, req.getId()));
-            reservedCount++;
-        }
         withdrawalLogService.log(req.getTenantId(), clerkId, req.getId(),
                 "RESERVED", req.getStatus(), req.getStatus(),
                 "冻结收益已预留，条数=" + reservedCount + ", 金额=" + amount, null);

play-admin/src/main/resources/db/migration/V10__dedupe_and_unique_earnings_line.sql

@@ -0,0 +1,18 @@
+-- Remove duplicate earnings lines per tenant/order/clerk/type and add unique constraint
+
+DELETE FROM `play_earnings_line`
+WHERE `id` IN (
+    SELECT dup_id FROM (
+        SELECT id AS dup_id,
+               ROW_NUMBER() OVER (
+                   PARTITION BY tenant_id, order_id, clerk_id, earning_type
+                   ORDER BY created_time, id
+               ) AS rn
+        FROM `play_earnings_line`
+        WHERE deleted = 0
+    ) ranked
+    WHERE ranked.rn > 1
+);
+
+ALTER TABLE `play_earnings_line`
+    ADD UNIQUE KEY `uk_tenant_order_clerk_type` (`tenant_id`, `order_id`, `clerk_id`, `earning_type`, `deleted`);