fix: Mishandling of scheduled_at in gql

src/ai/backend/manager/models/kernel.py

@@ -75,7 +75,6 @@
 )
 from .group import groups
 from .image import ImageNode
-from .minilang import JSONFieldItem
 from .minilang.ordering import ColumnMapType, QueryOrderParser
 from .minilang.queryfilter import FieldSpecType, QueryFilterParser, enum_field_getter
 from .user import users
@@ -870,7 +869,7 @@ def parse_row(cls, ctx: GraphQueryContext, row: KernelRow) -> Mapping[str, Any]:
             "created_at": row.created_at,
             "terminated_at": row.terminated_at,
             "starts_at": row.starts_at,
-            "scheduled_at": scheduled_at or None,
+            "scheduled_at": scheduled_at,
             "occupied_slots": row.occupied_slots.to_json(),
             # resources
             "agent": row.agent if not hide_agents else None,
@@ -924,7 +923,7 @@ async def resolve_abusing_report(
         "created_at": ("created_at", dtparse),
         "status_changed": ("status_changed", dtparse),
         "terminated_at": ("terminated_at", dtparse),
-        "scheduled_at": (JSONFieldItem("status_history", KernelStatus.SCHEDULED.name), dtparse),
+        "scheduled_at": ("scheduled_at", None),
     }
 
     _queryorder_colmap: ColumnMapType = {
@@ -941,7 +940,7 @@ async def resolve_abusing_report(
         "status_changed": ("status_info", None),
         "created_at": ("created_at", None),
         "terminated_at": ("terminated_at", None),
-        "scheduled_at": (JSONFieldItem("status_history", KernelStatus.SCHEDULED.name), None),
+        "scheduled_at": ("scheduled_at", None),
     }
 
     @classmethod