fix(referral): 修复 getReferralChain API 返回 accountSequence 而非 userId

- 修改 getReferralChain 方法返回的 ancestorPath 为 accountSequence 格式
- 修改 getBatchReferralChains 方法同样返回 accountSequence 格式
- 这修复了 authorization-service 查询社区层级时使用错误格式的问题
- 之前返回 userId (如 "25121400000")，现在返回 accountSequence (如 "D25121400000")

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/services/referral-service/src/api/controllers/internal-referral-chain.controller.ts

@@ -58,8 +58,21 @@ export class InternalReferralChainController {
       };
     }
 
-    // ancestorPath 存储的是 userId (bigint)，需要转换为字符串
-    const ancestorPath = relationship.referralChain.map((id) => id.toString());
+    // referralChain 存储的是 userId (bigint)，需要转换为 accountSequence
+    // 因为 authorization-service 使用 accountSequence 来查询授权记录
+    const ancestorUserIds = relationship.referralChain;
+    const ancestorPath: string[] = [];
+
+    for (const ancestorUserId of ancestorUserIds) {
+      const ancestorRelationship = await this.referralRepo.findByUserId(ancestorUserId);
+      if (ancestorRelationship) {
+        ancestorPath.push(ancestorRelationship.accountSequence);
+      } else {
+        this.logger.warn(`[INTERNAL] Ancestor userId ${ancestorUserId} not found`);
+      }
+    }
+
+    this.logger.debug(`[INTERNAL] getReferralChain result: ${ancestorPath.length} ancestors`);
 
     return {
       accountSequence: relationship.accountSequence,
@@ -88,9 +101,18 @@ export class InternalReferralChainController {
     for (const seq of sequences) {
       const relationship = await this.referralRepo.findByAccountSequence(seq);
       if (relationship) {
+        // 转换 userId 为 accountSequence
+        const ancestorPath: string[] = [];
+        for (const ancestorUserId of relationship.referralChain) {
+          const ancestorRelationship = await this.referralRepo.findByUserId(ancestorUserId);
+          if (ancestorRelationship) {
+            ancestorPath.push(ancestorRelationship.accountSequence);
+          }
+        }
+
         results[seq] = {
           userId: relationship.userId.toString(),
-          ancestorPath: relationship.referralChain.map((id) => id.toString()),
+          ancestorPath,
           referrerId: relationship.referrerId?.toString() ?? null,
         };
       } else {