feat: add per-account empty response tracking with email in logs

Track empty_response_count per account in AccountUsage, exposed via
GET /auth/accounts. Logs now include account email for easier debugging.
Counter resets on usage reset and rate limit window rollover.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,8 @@
 
 ### Added
 
+- 空响应计数器：每个账号追踪 `empty_response_count`，通过 `GET /auth/accounts` 可查看，窗口重置时自动归零
+- 空响应日志增强：日志中显示账号邮箱（`Account xxxx (email) | Empty response`），便于定位问题账号
 - 空响应检测 + 自动换号重试：Codex API 返回 HTTP 200 但无内容时，非流式自动切换账号重试（最多 3 次），流式注入错误提示文本
 - 自动提取 Chromium 版本：`extract-fingerprint.ts` 从 `package.json` 读取 Electron 版本，通过 `electron-to-chromium` 映射为 Chromium 大版本，`apply-update.ts` 自动更新 `chromium_version` 和 TLS impersonate profile
 - 动态模型列表：后台从 Codex 后端自动获取模型目录，与静态 YAML 合并（`src/models/model-store.ts`、`src/models/model-fetcher.ts`）
@@ -28,6 +30,7 @@
 
 ### Fixed
 
+- 空响应重试循环中账号双重释放：外层 catch 使用原始 `entryId` 而非当前活跃账号，导致换号重试失败时 double-release（`proxy-handler.ts`）
 - `apply-update.ts` 模型比较不再误报删除：静态提取只含 2 个硬编码模型，与 YAML 的 24 个比较会产生 22 个假删除，现在只报新增
 - `update-checker.ts` 子进程超时保护：`fork()` 添加 5 分钟 kill timer，防止挂起导致 `_updateInProgress` 永久锁定
 - `model-fetcher.ts` 初始定时器添加 try/finally，防止异常中断刷新循环

src/auth/account-pool.ts

@@ -203,6 +203,7 @@ export class AccountPool {
         request_count: 0,
         input_tokens: 0,
         output_tokens: 0,
+        empty_response_count: 0,
         last_used: null,
         rate_limit_until: null,
       },
@@ -214,6 +215,16 @@ export class AccountPool {
     return id;
   }
 
+  /**
+   * Record an empty response for an account (HTTP 200 but zero text deltas).
+   */
+  recordEmptyResponse(entryId: string): void {
+    const entry = this.accounts.get(entryId);
+    if (!entry) return;
+    entry.usage.empty_response_count++;
+    this.schedulePersist();
+  }
+
   removeAccount(id: string): boolean {
     this.acquireLocks.delete(id);
     const deleted = this.accounts.delete(id);
@@ -254,6 +265,7 @@ export class AccountPool {
       request_count: 0,
       input_tokens: 0,
       output_tokens: 0,
+      empty_response_count: 0,
       last_used: null,
       rate_limit_until: null,
       window_reset_at: entry.usage.window_reset_at ?? null,
@@ -279,6 +291,7 @@ export class AccountPool {
       entry.usage.request_count = 0;
       entry.usage.input_tokens = 0;
       entry.usage.output_tokens = 0;
+      entry.usage.empty_response_count = 0;
       entry.usage.last_used = null;
       entry.usage.rate_limit_until = null;
     }
@@ -466,6 +479,11 @@ export class AccountPool {
                 needsPersist = true;
               }
             }
+            // Backfill empty_response_count for old entries
+            if (entry.usage.empty_response_count == null) {
+              entry.usage.empty_response_count = 0;
+              needsPersist = true;
+            }
             this.accounts.set(entry.id, entry);
           }
         }
@@ -505,6 +523,7 @@ export class AccountPool {
           request_count: 0,
           input_tokens: 0,
           output_tokens: 0,
+          empty_response_count: 0,
           last_used: null,
           rate_limit_until: null,
         },

src/auth/types.ts

@@ -13,6 +13,7 @@ export interface AccountUsage {
   request_count: number;
   input_tokens: number;
   output_tokens: number;
+  empty_response_count: number;
   last_used: string | null;
   rate_limit_until: string | null;
   /** Tracks the current rate limit window end (Unix seconds). When window rolls over, counters reset. */

src/routes/shared/proxy-handler.ts

@@ -174,9 +174,11 @@ export async function handleProxyRequest(
           return c.json(result.response);
         } catch (collectErr) {
           if (collectErr instanceof EmptyResponseError && attempt <= MAX_EMPTY_RETRIES) {
+            const emptyEmail = accountPool.getEntry(currentEntryId)?.email ?? "?";
             console.warn(
-              `[${fmt.tag}] Account ${currentEntryId} | Empty response (attempt ${attempt}/${MAX_EMPTY_RETRIES + 1}), switching account...`,
+              `[${fmt.tag}] Account ${currentEntryId} (${emptyEmail}) | Empty response (attempt ${attempt}/${MAX_EMPTY_RETRIES + 1}), switching account...`,
             );
+            accountPool.recordEmptyResponse(currentEntryId);
             accountPool.release(currentEntryId, collectErr.usage);
 
             // Acquire a new account
@@ -210,9 +212,11 @@ export async function handleProxyRequest(
           // Not an empty response error, or retries exhausted
           accountPool.release(currentEntryId);
           if (collectErr instanceof EmptyResponseError) {
+            const exhaustedEmail = accountPool.getEntry(currentEntryId)?.email ?? "?";
             console.warn(
-              `[${fmt.tag}] Account ${currentEntryId} | Empty response (attempt ${attempt}/${MAX_EMPTY_RETRIES + 1}), all retries exhausted`,
+              `[${fmt.tag}] Account ${currentEntryId} (${exhaustedEmail}) | Empty response (attempt ${attempt}/${MAX_EMPTY_RETRIES + 1}), all retries exhausted`,
             );
+            accountPool.recordEmptyResponse(currentEntryId);
             c.status(502);
             return c.json(fmt.formatError(502, "Codex returned empty responses across all available accounts"));
           }