Register missing trail and food-category ViewSets in API router

TrailViewSet and FoodCategoryViewSet were imported but never registered
in the DRF router, causing HyperlinkedModelSerializer to fail when
trying to generate URLs for scrobble relationships.

Changes:
- Add router.register(r'trails', TrailViewSet)
- Add router.register(r'food-categories', FoodCategoryViewSet)

vrobbler/urls.py

@@ -125,6 +125,7 @@ router.register(r"profiles", UserProfileViewSet)
 router.register(r"domains", DomainViewSet)
 router.register(r"webpages", WebPageViewSet)
 router.register(r"foods", FoodViewSet)
+router.register(r"food-categories", FoodCategoryViewSet)
 router.register(r"moods", MoodViewSet)
 router.register(r"tasks", TaskViewSet)
 router.register(r"locations", GeoLocationViewSet)
@@ -155,6 +156,7 @@ router.register(r"birds", BirdViewSet)
 router.register(r"birding-locations", BirdingLocationViewSet)
 router.register(r"disc-golf-courses", DiscGolfCourseViewSet)
 router.register(r"observations", SpeciesObservationViewSet)
+router.register(r"trails", TrailViewSet)
 urlpatterns = [
     path("api/v1/", include(router.urls)),
     path("api/v1/auth", include("rest_framework.urls")),