fix: audit batch 2 visibility (I-1 shadow dropped rows, I-2 partial policy failure, I-5 failure policy table)

- I-1: evaluate_shadow counts dropped rows by cause (unparseable /
  unknown_tier / explicit / duplicate) with the identity
  audit_rows_total == routed_task_n + dropped_total; the shadow
  endpoint passes created_at/id through and reports audit totals
  next to sample counts.
- I-2 (option b): parse logs a warning naming each tier dropped for
  an invalid mode/requires; load attaches partial_failures to the
  policy; the worker records a task-level
  worker_routing_policy_load_failed audit for partial failures
  (same action as full failure, detail says failure=partial);
  the shadow report carries the policy fingerprint, dropped tiers
  and partial failures (no task context on that path, so no
  task-level audit there).
- I-5: coordinator gate audit lookup failure now raises
  _CoordGateLookupFailed and the merge converts it to escalate
  (no requeue, no round consumed); persisted-model lookup failure
  and required-tools check failure each write a named audit row
  before falling through to dispatch/allow; audit-loop evaluate
  failure stays escalate (regression test).
- Test fixtures: coordinator suites build audit_log via AuthStore
  as production's first real audit does, since their stubbed
  _audit never creates the table.

cloud/tests/test_audit_loop_coord.py

@@ -28,11 +28,13 @@ from types import SimpleNamespace
 
 try:
     from cloud.audit_loop import Finding
+    from cloud.auth import AuthStore
     from cloud.server import init_db
     from cloud.worker import Worker
 except ImportError:
     sys.path.insert(0, str(Path(__file__).resolve().parents[2]))
     from cloud.audit_loop import Finding
+    from cloud.auth import AuthStore
     from cloud.server import init_db
     from cloud.worker import Worker
 
@@ -100,6 +102,14 @@ class CoordAuditTestCase(unittest.TestCase):
         self.tmp = tempfile.TemporaryDirectory()
         self.db_path = os.path.join(self.tmp.name, "control.db")
         init_db(self.db_path)
+        # Audit batch 2 (I-5): 合流的门拒绝审计查询失败时走
+        # escalate，不再回落空集。生产里 audit_log 由首次
+        # 真实 _audit 经 AuthStore 建好，合流时表一定存在；
+        # 本文件把 _audit 桩成列表，表永远不会出现，所以
+        # 在夹具里按生产实际补建表——否则所有合流测试都会
+        # 因缺表改走 escalate，与被测行为无关。
+        _store = AuthStore(self.db_path)
+        _store.conn.close()
         self.env = {"XCM_API_KEY": "test-placeholder"}
         self.audits = []
         self.worker = self._worker()
@@ -399,8 +409,13 @@ class CoordAuditTestCase(unittest.TestCase):
                 "CREATE TABLE IF NOT EXISTS audit_log(user_id TEXT,"
                 " project_id TEXT, action TEXT, detail TEXT,"
                 " created_at DOUBLE PRECISION)")
+            # Audit batch 2 (I-5)：setUp 已按生产实际经 AuthStore
+            # 建好含 id 列的 audit_log 表，INSERT 必须显式列名，
+            # 否则在 6 列的生产表上会因 5 个值报错；显式列名在
+            # 旧 5 列手工表上同样成立。
             conn.execute(
-                "INSERT INTO audit_log VALUES('system', 'p1',"
+                "INSERT INTO audit_log(user_id, project_id, action,"
+                " detail, created_at) VALUES('system', 'p1',"
                 " 'worker_tool_gate_rejected',"
                 " 'C1: agent 声明必需工具缺失：websearch', ?)",
                 (time.time(),))