[feat] implementation of Wikimedia commons for images

searx/settings.yml

@@ -1640,6 +1640,12 @@ engines:
       website: https://www.wikivoyage.org/
       wikidata_id: Q373
 
+  - name: wikicommons.images
+    engine: wikicommons
+    shortcut: wc
+    categories: images
+    number_of_results: 10
+
   - name: wolframalpha
     shortcut: wa
     # You can use the engine using the official stable API, but you need an API