feat: Add DELETE /{slug}/image (#6259)

Co-authored-by: Michael Genson <71845777+michael-genson@users.noreply.github.com>

mealie/repos/repository_recipes.py

@@ -154,6 +154,11 @@ class RepositoryRecipes(HouseholdRepositoryGeneric[Recipe, RecipeModel]):
 
         return entry.image
 
+    def delete_image(self, slug: str, _: str | None = None):
+        entry: RecipeModel = self._query_one(match_value=slug)
+        entry.image = None
+        self.session.commit()
+
     def count_uncategorized(self, count=True, override_schema=None):
         return self._count_attribute(
             attribute_name=RecipeModel.recipe_category,