feat: 流式空闲超时、健康监控查询优化、限流桶内存上限与维护清理修复

Close #233

Co-authored-by: AAEE86 <ppk0227@hotmail.com>

- cli_monitor_mixin: 引入 STREAM_IDLE_TIMEOUT_SECONDS（可通过环境变量配置），
  流传输开始后若超出空闲窗口无新 chunk 则提前取消并返回 504，避免长时间挂起
- stream_context: 新增 managed_recorded_bodies 上下文管理器，确保 chunks 在
  telemetry 完成后及时释放；stream_telemetry 使用该接口统一管理 response body 构建
- health endpoint: 将状态聚合改为 GROUP BY 直接统计，事件列表按 api_format
  单独查询，避免单次 limit 拉取大量记录导致的遗漏与性能问题；同时过滤不活跃
  provider/endpoint，与公开健康接口保持一致
- endpoint health service: 修正时间线数据按 endpoint_id 而非 key_id 聚合
- token_bucket: 引入 max_buckets/bucket_expiry 上限与定时清理，防止内存无限增长；
  修复 refill_rate=0 时 get_reset_time 除零异常；新增 _is_unlimited_rate_limit 判断
- maintenance_scheduler: 调整清理顺序（先删整行再按窗口清理），新增 newer_than
  边界参数，避免同一行在同一轮中被重复改写
- sync_execute: 新增 create_pending_usage 开关，允许已预创建记录的调用方跳过重复创建
- quota_reader / provider_ops balance: 小幅修复与健壮性提升
- Dockerfile: 添加 MALLOC_ARENA_MAX=2 环境变量以降低 gunicorn worker RSS
- 补充相关测试覆盖

tests/api/test_health_monitor_api_formats.py

@@ -0,0 +1,146 @@
+from __future__ import annotations
+
+from datetime import datetime, timezone
+from types import SimpleNamespace
+from typing import Any, cast
+from unittest.mock import MagicMock
+
+import pytest
+
+from src.api.admin.endpoints.health import AdminApiFormatHealthMonitorAdapter
+from src.api.public.catalog import PublicApiFormatHealthMonitorAdapter
+
+
+def _build_query(result: object) -> MagicMock:
+    query = MagicMock()
+    query.join.return_value = query
+    query.distinct.return_value = query
+    query.filter.return_value = query
+    query.group_by.return_value = query
+    query.order_by.return_value = query
+    query.limit.return_value = query
+    query.all.return_value = result
+    return query
+
+
+def _expr_texts(query: MagicMock) -> list[str]:
+    return [str(arg) for arg in query.filter.call_args.args]
+
+
+@pytest.mark.asyncio
+async def test_admin_api_format_health_monitor_filters_inactive_sources(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    endpoint_query = _build_query([("openai:compact", "ep-active", "provider-active")])
+    key_query = _build_query([("provider-active", ["openai:compact"])])
+    status_query = _build_query([("openai:compact", "success", 3)])
+    rows_query = _build_query([])
+
+    db = MagicMock()
+    db.query.side_effect = [endpoint_query, key_query, status_query, rows_query]
+
+    monkeypatch.setattr(
+        "src.api.admin.endpoints.health.EndpointHealthService._generate_timeline_from_usage",
+        lambda **_: {
+            "timeline": ["healthy"] * 100,
+            "time_range_start": None,
+            "time_range_end": None,
+        },
+    )
+
+    context = SimpleNamespace(
+        db=db,
+        request=SimpleNamespace(state=SimpleNamespace()),
+        add_audit_metadata=lambda **kwargs: None,
+    )
+
+    adapter = AdminApiFormatHealthMonitorAdapter(lookback_hours=6, per_format_limit=20)
+    await adapter.handle(cast(Any, context))
+
+    status_filters = _expr_texts(status_query)
+    rows_filters = _expr_texts(rows_query)
+
+    assert any("provider_endpoints.is_active" in expr for expr in status_filters)
+    assert any("providers.is_active" in expr for expr in status_filters)
+    assert any("provider_endpoints.is_active" in expr for expr in rows_filters)
+    assert any("providers.is_active" in expr for expr in rows_filters)
+
+
+@pytest.mark.asyncio
+async def test_public_api_format_health_monitor_uses_real_counts_not_sampled_events(
+    monkeypatch: pytest.MonkeyPatch,
+) -> None:
+    now = datetime.now(timezone.utc)
+    active_formats_query = _build_query([("openai:compact",)])
+    endpoint_rows_query = _build_query([("openai:compact", "ep-active")])
+    status_query = _build_query(
+        [
+            ("openai:compact", "success", 7),
+            ("openai:compact", "failed", 3),
+            ("openai:compact", "skipped", 5),
+        ]
+    )
+    rows_query = _build_query(
+        [
+            SimpleNamespace(
+                status="failed",
+                status_code=500,
+                latency_ms=321,
+                error_type="provider_error",
+                finished_at=now,
+                started_at=None,
+                created_at=now,
+            ),
+            SimpleNamespace(
+                status="success",
+                status_code=200,
+                latency_ms=123,
+                error_type=None,
+                finished_at=now,
+                started_at=None,
+                created_at=now,
+            ),
+        ]
+    )
+
+    db = MagicMock()
+    db.query.side_effect = [
+        active_formats_query,
+        endpoint_rows_query,
+        status_query,
+        rows_query,
+    ]
+
+    monkeypatch.setattr(
+        "src.api.public.catalog.EndpointHealthService._generate_timeline_from_usage",
+        lambda **_: {
+            "timeline": ["healthy"] * 100,
+            "time_range_start": None,
+            "time_range_end": now,
+        },
+    )
+    monkeypatch.setattr(
+        "src.core.api_format.get_local_path_for_endpoint",
+        lambda api_format: f"/{api_format}",
+    )
+
+    context = SimpleNamespace(
+        db=db,
+        request=SimpleNamespace(state=SimpleNamespace()),
+    )
+
+    adapter = PublicApiFormatHealthMonitorAdapter(lookback_hours=6, per_format_limit=20)
+    result = await adapter.handle(cast(Any, context))
+
+    monitor = result["formats"][0]
+    assert monitor["api_format"] == "openai:compact"
+    assert monitor["total_attempts"] == 15
+    assert monitor["success_count"] == 7
+    assert monitor["failed_count"] == 3
+    assert monitor["skipped_count"] == 5
+    assert monitor["success_rate"] == pytest.approx(0.7)
+    assert len(monitor["events"]) == 2
+
+    rows_filters = _expr_texts(rows_query)
+    assert any("provider_endpoints.is_active" in expr for expr in rows_filters)
+    assert any("providers.is_active" in expr for expr in rows_filters)