feat: 引入 status_snapshot 统一 provider key 状态管理

- 新增 StatusSnapshot 模型，聚合 OAuth / 账号 / 配额三维状态
- 新增 StatusSnapshotStore 负责快照的持久化与查询
- 重构 response_builder / endpoint_models，基于 snapshot 输出状态字段
- 前端抽取 providerKeyStatus / oauthRefreshFeedback 工具函数，
  统一 PoolManagement、ProviderDetailDrawer、BatchDialog 的状态展示
- errorParser 增加已知 OAuth 错误的友好提示
- refresher 适配 snapshot 写入，account_state 扩展状态分类
- 新增 alembic 迁移及存量数据回填脚本
- 补充前后端单元测试

tests/unit/test_provider_key_response_builder.py

@@ -18,7 +18,7 @@ def test_build_key_response_includes_codex_identity_metadata(
         api_formats=["openai:chat"],
         auth_type="oauth",
         api_key="enc-access-token",
-        auth_config='{"email":"u@example.com","plan_type":"team","account_id":"acc-1","account_name":"Workspace Alpha","account_user_id":"user-1__acc-1","organizations":[{"id":"org-1","title":"Personal","is_default":true,"role":"owner"}],"expires_at":123456}',
+        auth_config='{"email":"u@example.com","plan_type":"team","account_id":"acc-1","account_name":"Workspace Alpha","account_user_id":"user-1__acc-1","organizations":[{"id":"org-1","title":"Personal","is_default":true,"role":"owner"}],"expires_at":2100000000}',
         name="codex-user",
     )
     now = datetime.now(timezone.utc)
@@ -54,3 +54,63 @@ def test_build_key_response_includes_codex_identity_metadata(
     assert len(result.oauth_organizations) == 1
     assert result.oauth_organizations[0].title == "Personal"
     assert result.oauth_organizations[0].is_default is True
+    assert result.status_snapshot.oauth.code == "valid"
+    assert result.status_snapshot.oauth.expires_at == 2100000000
+    assert result.status_snapshot.account.code == "ok"
+
+
+def test_build_key_response_prefers_persisted_status_snapshot_layers(
+    monkeypatch: "pytest.MonkeyPatch",
+) -> None:
+    key = ProviderAPIKey(
+        id="key-2",
+        provider_id="provider-1",
+        api_formats=["openai:chat"],
+        auth_type="oauth",
+        api_key="enc-access-token",
+        auth_config='{"expires_at":100}',
+        name="codex-user",
+        status_snapshot={
+            "oauth": {"code": "valid", "label": "有效", "expires_at": 100},
+            "account": {
+                "code": "workspace_deactivated",
+                "label": "工作区停用",
+                "reason": "persisted",
+                "blocked": True,
+            },
+            "quota": {
+                "code": "exhausted",
+                "label": "额度耗尽",
+                "reason": "persisted quota",
+                "exhausted": True,
+            },
+        },
+    )
+    now = datetime.now(timezone.utc)
+    key.success_count = 0
+    key.request_count = 0
+    key.error_count = 0
+    key.total_response_time_ms = 0
+    key.rpm_limit = None
+    key.global_priority_by_format = None
+    key.allowed_models = None
+    key.capabilities = None
+    key.is_active = True
+    key.created_at = now
+    key.updated_at = now
+    key.cache_ttl_minutes = 5
+    key.max_probe_interval_minutes = 32
+    key.health_by_format = None
+    key.circuit_breaker_by_format = None
+    key.oauth_invalid_at = None
+    key.oauth_invalid_reason = None
+    key.note = None
+    key.last_used_at = None
+
+    monkeypatch.setattr(module.crypto_service, "decrypt", lambda value: value)
+
+    result = build_key_response(key)
+
+    assert result.status_snapshot.oauth.code == "expired"
+    assert result.status_snapshot.account.code == "workspace_deactivated"
+    assert result.status_snapshot.quota.code == "exhausted"