feat: add ids-filter to show, schedule and timeslot endpoints

This makes it easy to list entries with specific ids, which comes in
handy when clients want to fetch multiple known objects at once.

program/filters.py

@@ -57,6 +57,10 @@ class ShowOrderingFilter(filters.OrderingFilter):
 
 
 class ShowFilterSet(StaticFilterHelpTextMixin, filters.FilterSet):
+    ids = IntegerInFilter(
+        field_name="id",
+        help_text="Return only shows matching the specified id(s).",
+    )
     order = ShowOrderingFilter(
         fields=["name", "slug", "id", "is_active", "is_owner", "updated_at", "updated_by"],
         help_text="Order shows by the given field(s).",
@@ -131,6 +135,7 @@ class ShowFilterSet(StaticFilterHelpTextMixin, filters.FilterSet):
     class Meta:
         model = models.Show
         fields = [
+            "ids",
             "order",
             "category_ids",
             "category_slug",
@@ -150,6 +155,10 @@ class ShowFilterSet(StaticFilterHelpTextMixin, filters.FilterSet):
 
 
 class ScheduleFilterSet(filters.FilterSet):
+    ids = IntegerInFilter(
+        field_name="id",
+        help_text="Return only schedules matching the specified id(s).",
+    )
     show_ids = IntegerInFilter(
         field_name="show",
         help_text="Return only schedules that belong to the specified show(s).",
@@ -171,6 +180,10 @@ class ScheduleFilterSet(filters.FilterSet):
 
 
 class TimeSlotFilterSet(filters.FilterSet):
+    ids = IntegerInFilter(
+        field_name="id",
+        help_text="Return only timeslots matching the specified id(s).",
+    )
     order = filters.OrderingFilter(
         fields=[field.name for field in models.TimeSlot._meta.get_fields()]
     )
@@ -237,6 +250,7 @@ class TimeSlotFilterSet(filters.FilterSet):
     class Meta:
         model = models.TimeSlot
         fields = [
+            "ids",
             "order",
             "start",
             "end",