R15: Fix D04/D06/D07 partial completion

D04: Add fish name-based fallback in _auto_publish (was external_id only)
D06: Cap confidence at 50% for 1 player, 65% for 2 players
D07: Set caught_at=None for community imports (not published_at)
D08: Already OK - activity_rows has no top-100 limit

- Add Fish import to community_importer.py
- Add 2 unit tests for D06 confidence caps
- Update test_community_importer.py for D04 name match behavior

apps/api/tests/test_community_importer.py

@@ -116,9 +116,11 @@ def test_changed_published_record_requires_review_and_reuses_report(db: Session)
     water = Waterbody(slug="test-lake", name_ru="Тестовое озеро")
     db.add_all([fish, water])
     db.commit()
+    # D04: auto-publish now works with name match fallback
     stage_observations(db, [record() | {"weight_g": 5000}])
     item = db.scalar(select(ExternalObservation))
-    map_observation(db, item, fish, water)
+    # Item auto-published via name match fallback (D04)
+    assert item.status == "published"
     report = publish_observation(db, item)
     report_id = report.id
     stage_observations(db, [record() | {"weight_g": 6000}])