Process potential children of literary collections later

I've had some nondeterministic behavior with
https://www.wikidata.org/wiki/Q7755407 which is a child of both
https://www.wikidata.org/wiki/Q3399570 and
https://www.wikidata.org/wiki/Q3232655 and I think this will make it
deterministic.

rock_paper_sand/wikidata.py

@@ -129,10 +129,14 @@ class _RelatedMediaPriority(enum.IntEnum):
         UNLIKELY: Unlikely to be processed. E.g., TV episodes are likely to be
             integral children of TV shows, so they're unlikely to be processed
             any further.
+        POSSIBLE: Might or might not be processed. E.g., short stories are
+            sometimes integral children of books that have multiple related
+            short stories.
         LIKELY: Likely to be processed, because none of the above applies.
     """
 
     UNLIKELY = enum.auto()
+    POSSIBLE = enum.auto()
     LIKELY = enum.auto()
 
 
@@ -651,6 +655,15 @@ def _priority_by_classes(
                     ),
                 },
             ),
+            (
+                _RelatedMediaPriority.POSSIBLE,
+                {
+                    *self._api.transitive_subclasses(wikidata_value.Q_NOVELLA),
+                    *self._api.transitive_subclasses(
+                        wikidata_value.Q_SHORT_STORY
+                    ),
+                },
+            ),
         )
 
     def _is_ignored(
@@ -863,6 +876,7 @@ def _related_media(
             _RelatedMediaPriority, set[wikidata_value.ItemRef]
         ] = {
             _RelatedMediaPriority.UNLIKELY: set(),
+            _RelatedMediaPriority.POSSIBLE: set(),
             _RelatedMediaPriority.LIKELY: {request.item.wikidata_item},
         }
         processed: set[wikidata_value.ItemRef] = set()

rock_paper_sand/wikidata_value.py

@@ -147,6 +147,7 @@ def human_readable_url_prefix(cls) -> str:
 Q_LIST = _i("https://www.wikidata.org/wiki/Q12139612")
 Q_LITERARY_WORK = _i("https://www.wikidata.org/wiki/Q7725634")
 Q_MUSICAL_WORK = _i("https://www.wikidata.org/wiki/Q2188189")
+Q_NOVELLA = _i("https://www.wikidata.org/wiki/Q149537")
 Q_OMNIVERSE = _i("https://www.wikidata.org/wiki/Q116503898")
 Q_PARATEXT = _i("https://www.wikidata.org/wiki/Q853520")
 Q_PART_OF_TELEVISION_SEASON = _i("https://www.wikidata.org/wiki/Q93992677")
@@ -156,6 +157,7 @@ def human_readable_url_prefix(cls) -> str:
 Q_SEGMENT_OF_A_TELEVISION_EPISODE = _i(
     "https://www.wikidata.org/wiki/Q29555881"
 )
+Q_SHORT_STORY = _i("https://www.wikidata.org/wiki/Q49084")
 Q_TELEVISION_FILM = _i("https://www.wikidata.org/wiki/Q506240")
 Q_TELEVISION_PILOT = _i("https://www.wikidata.org/wiki/Q653916")
 Q_TELEVISION_SERIES = _i("https://www.wikidata.org/wiki/Q5398426")