fix(persistence): separate retryable rejection errors (#6423)

app/application/messaging/chat.py

@@ -12,10 +12,7 @@ from app.application.database import (
     AsyncDatabaseExecutor,
 )
 from app.schemas.agent import AgentChatSessionDetail, AgentChatSessionSummary
-from app.schemas.exception import (
-    DatabaseWorkerClosedError,
-    DatabaseWorkerOverloadedError,
-)
+from app.schemas.exception import AgentChatPersistenceUnavailableError
 from app.runtime.observability import record_metric
 
 
@@ -364,14 +361,16 @@ class AgentChatPersistenceService:
         """在线程 worker 内完成同步写入并丢弃仓储对象返回值。"""
         # 同时限制全局和单会话等待量，避免一个热点会话占满总 admission 后饿死其他会话。
         if self._closing:
-            raise DatabaseWorkerClosedError("AgentChat 持久化服务当前不可接收任务")
+            raise AgentChatPersistenceUnavailableError(
+                "AgentChat 持久化服务当前不可接收任务"
+            )
         session_pending = self._pending_by_session.get(session_id, 0)
         if (
             self._pending_writes >= self._capacity
             or session_pending >= self._session_capacity
         ):
             record_metric("agent.chat.persistence.rejected")
-            raise DatabaseWorkerOverloadedError(
+            raise AgentChatPersistenceUnavailableError(
                 f"AgentChat 写入容量已用尽（全局上限 {self._capacity}，"
                 f"单会话上限 {self._session_capacity}）"
             )

app/application/plugin/install.py

@@ -7,7 +7,7 @@ from collections.abc import Awaitable, Callable
 from dataclasses import dataclass, field
 from typing import Any, Optional
 
-from app.schemas.exception import DatabaseWorkerOverloadedError
+from app.schemas.exception import PersistenceUnavailableError
 from app.application.plugin.lifecycle import plugin_lifecycle
 from app.runtime.log import logger
 
@@ -196,7 +196,7 @@ class PluginInstallCommand:
                 message=str(err),
                 package_installed=False,
             )
-            if isinstance(err, DatabaseWorkerOverloadedError):
+            if isinstance(err, PersistenceUnavailableError):
                 raise
             return result
         if not package_installed:
@@ -228,7 +228,7 @@ class PluginInstallCommand:
                     package_installed=True,
                     installed_list_persisted=state.installed_list_touched,
                 )
-                if isinstance(err, DatabaseWorkerOverloadedError):
+                if isinstance(err, PersistenceUnavailableError):
                     raise
                 return result
 
@@ -247,7 +247,7 @@ class PluginInstallCommand:
                 installed_list_persisted=installed_list_persisted,
                 runtime_touched=True,
             )
-            if isinstance(err, DatabaseWorkerOverloadedError):
+            if isinstance(err, PersistenceUnavailableError):
                 raise
             return result
 
@@ -267,7 +267,7 @@ class PluginInstallCommand:
                 runtime_touched=True,
                 registrations_touched=True,
             )
-            if isinstance(err, DatabaseWorkerOverloadedError):
+            if isinstance(err, PersistenceUnavailableError):
                 raise
             return result
 
@@ -412,7 +412,7 @@ class PluginInstallCommand:
                 failure_stage=failure_stage,
                 rollback=rollback,
             )
-            if isinstance(err, DatabaseWorkerOverloadedError):
+            if isinstance(err, PersistenceUnavailableError):
                 raise
             return result