UX: Add proper attribution to illustrate post images (#398)

config/locales/server.en.yml

@@ -128,6 +128,8 @@ en:
         custom_prompt: "Custom Prompt"
         explain: "Explain"
         illustrate_post: "Illustrate Post"
+      painter:
+        attribution: "Image by Stable Diffusion XL"
 
     ai_bot:
       personas:

lib/ai_helper/painter.rb

@@ -20,7 +20,10 @@ module DiscourseAi
           f.binmode
           f.write(Base64.decode64(artifact))
           f.rewind
-          upload = UploadCreator.new(f, "ai_helper_image_#{i}.png").create_for(user.id)
+          upload =
+            UploadCreator.new(f, I18n.t("discourse_ai.ai_helper.painter.attribution")).create_for(
+              user.id,
+            )
           f.unlink
 
           UploadSerializer.new(upload, root: false)