M3a：息壤三级记忆域——归真触发提取管线/白名单明忆/重忆确认/正影版本链/删除墓碑/双通道召回注入，退役旧记忆-抽取-反思-大周天-演化管线（迁移 004，验收 7 用例）

backend/app/services/admin.py

@@ -21,7 +21,7 @@ from app.models.governance import (
     WorldEntity,
 )
 from app.models.idempotency import IdempotencyKey
-from app.models.memory import Memory
+from app.models.xirang import Memory
 from app.models.runtime import Event, Run
 from app.models.safety import AuditEvent
 from app.modules.safety.confirmation import ConfirmationStore, PendingConfirmation
@@ -77,7 +77,7 @@ async def get_pivots_health(
         plans_n = await governance_repo.count(session, Plan)
         perception_n = await governance_repo.count(session, PerceptionChannel)
         agents_n = await governance_repo.count(session, AgentRosterEntry)
-        memories_n = await governance_repo.count(session, Memory)
+        memories_n = await governance_repo.count(session, Memory, Memory.status != "tombstoned")
         character = await character_repo.get_active_character(session, owner_scope)
         has_personality = bool(character and character.current_personality_version_id)
         tool_enabled = settings.enable_tool_runtime and tool_runtime is not None