Add JSON integrity hash checks

src/ccma/domain/models.py

@@ -295,10 +295,12 @@ class ContributionData:
 @dataclass(frozen=True, slots=True)
 class HousekeeperFinding:
     severity: str
-    member_id: str
     code: str
     title: str
     detail: str
+    member_id: str = ""
+    asset_id: str = ""
+    target_type: str = "member"
     due_date: date | None = None
     key: str = ""