feat: add bulk moderation decisions

apps/api/app/schemas.py

@@ -326,6 +326,28 @@ class ModerationUpdate(BaseModel):
         return value
 
 
+class ModerationBulkItem(BaseModel):
+    id: UUID
+    expected_version: int = Field(ge=0)
+
+
+class ModerationBulkUpdate(BaseModel):
+    status: str
+    reason: str | None = Field(default=None, max_length=1000)
+    items: list[ModerationBulkItem] = Field(min_length=1, max_length=50)
+
+    @field_validator("status")
+    @classmethod
+    def known_bulk_status(cls, value: str) -> str:
+        if value not in {"approved", "rejected", "pending"}:
+            raise ValueError("unknown moderation status")
+        return value
+
+
+class ModerationBulkResult(BaseModel):
+    updated: int
+
+
 class ExternalObservationOut(BaseModel):
     id: UUID
     source_system: str