Drop HistoryMinimal to preserve API behavior for "keys"

lib/galaxy/schema/schema.py

@@ -1204,16 +1204,15 @@ class UpdateHistoryContentsPayload(HistoryBase):
     )
 
 
-class HistoryMinimal(HistoryBase, WithModelClass):
-    """Minimal History Response with optional fields"""
+class CustomHistoryView(HistoryBase):
+    """History Response with all optional fields.
 
-    model_class: HISTORY_MODEL_CLASS = ModelClassField(HISTORY_MODEL_CLASS)
-    id: Optional[HistoryID] = None
-    user_id: Optional[EncodedDatabaseIdField] = Field(
-        None,
-        title="User ID",
-        description="The encoded ID of the user that owns this History.",
-    )
+    It is used for serializing only specific attributes using the "keys"
+    query parameter. Unfortunately, we cannot know the exact fields that
+    will be requested, so we have to allow all fields to be optional.
+    """
+
+    pass
 
 
 class HistorySummary(HistoryBase, WithModelClass):
@@ -1341,10 +1340,13 @@ class HistoryDetailed(HistorySummary):  # Equivalent to 'dev-detailed' view, whi
     )
 
 
-AnyHistoryView = Union[
-    HistoryDetailed,
-    HistorySummary,
-    HistoryMinimal,
+AnyHistoryView = Annotated[
+    Union[
+        HistorySummary,
+        HistoryDetailed,
+        CustomHistoryView,
+    ],
+    Field(union_mode="left_to_right"),
 ]