feat(pool,trace): 账号封禁原因细分与请求追踪 attempted_only 过滤

- 将账号封禁原因从笼统的"账号异常"细分为封禁/停用/需要验证三类，
  前后端关键词组同步拆分，号池管理页面展示对应分类标签
- trace API 新增 attempted_only 参数，支持仅返回实际尝试过的候选，
  前端时间线组件默认启用过滤，排除 available/unused/skipped 记录

tests/unit/test_monitoring_trace_attempted_subset.py

@@ -8,9 +8,16 @@ from unittest.mock import MagicMock
 from src.api.admin.monitoring.trace import AdminGetRequestTraceAdapter
 from src.services.request.candidate import RequestCandidateService
 
+_STARTED_STATUSES = {"pending", "streaming", "success", "failed", "cancelled"}
 
-def _candidate(*, status: str, latency_ms: int | None = None) -> SimpleNamespace:
+
+def _candidate(
+    *, status: str, latency_ms: int | None = None, started_at: datetime | None = ...  # type: ignore[assignment]
+) -> SimpleNamespace:
     now = datetime.now(timezone.utc)
+    resolved_started_at = (
+        (now if status in _STARTED_STATUSES else None) if started_at is ... else started_at
+    )
     return SimpleNamespace(
         id=f"cand-{status}",
         request_id="req-1",
@@ -30,7 +37,7 @@ def _candidate(*, status: str, latency_ms: int | None = None) -> SimpleNamespace
         concurrent_requests=None,
         extra_data=None,
         created_at=now,
-        started_at=None,
+        started_at=resolved_started_at,
         finished_at=None,
     )
 
@@ -80,3 +87,46 @@ def test_trace_returns_unattempted_candidates(monkeypatch: object) -> None:
     assert response.total_candidates == 2
     assert len(response.candidates) == 2
     assert {c.status for c in response.candidates} == {"available", "unused"}
+
+
+def test_trace_attempted_only_filters_unattempted_candidates(monkeypatch: object) -> None:
+    candidates = [
+        _candidate(status="available"),
+        _candidate(status="unused"),
+        _candidate(status="skipped"),
+        _candidate(status="failed", latency_ms=123),
+        _candidate(status="success", latency_ms=456),
+    ]
+    monkeypatch.setattr(
+        RequestCandidateService,
+        "get_candidates_by_request_id",
+        lambda _db, _request_id: candidates,
+    )
+
+    adapter = AdminGetRequestTraceAdapter(request_id="req-1", attempted_only=True)
+    response = asyncio.run(adapter.handle(_context()))
+
+    assert response.total_candidates == 2
+    assert len(response.candidates) == 2
+    assert {c.status for c in response.candidates} == {"failed", "success"}
+    assert response.total_latency_ms == 579
+
+
+def test_trace_attempted_only_excludes_pending_without_started_at(monkeypatch: object) -> None:
+    candidates = [
+        _candidate(status="available"),
+        _candidate(status="pending", started_at=None),
+        _candidate(status="pending"),
+    ]
+    monkeypatch.setattr(
+        RequestCandidateService,
+        "get_candidates_by_request_id",
+        lambda _db, _request_id: candidates,
+    )
+
+    adapter = AdminGetRequestTraceAdapter(request_id="req-1", attempted_only=True)
+    response = asyncio.run(adapter.handle(_context()))
+
+    assert response.total_candidates == 1
+    assert len(response.candidates) == 1
+    assert response.candidates[0].status == "pending"