Support gpt-image-1 (#201)

Resolves #200 

Seems pretty simple to me. Borrowed the model passing idea from #152

Author: tpaulshippy

lib/ruby_llm/provider.rb

@@ -40,7 +40,7 @@ def embed(text, model:, connection:, dimensions:)
       def paint(prompt, model:, size:, connection:)
         payload = render_image_payload(prompt, model:, size:)
         response = connection.post images_url, payload
-        parse_image_response response
+        parse_image_response(response, model:)
       end
 
       def configured?(config = nil)

lib/ruby_llm/providers/gemini/images.rb

@@ -24,7 +24,7 @@ def render_image_payload(prompt, model:, size:)
           }
         end
 
-        def parse_image_response(response)
+        def parse_image_response(response, model:)
           data = response.body
           image_data = data['predictions']&.first
 
@@ -38,7 +38,8 @@ def parse_image_response(response)
 
           Image.new(
             data: base64_data,
-            mime_type: mime_type
+            mime_type: mime_type,
+            model_id: model
           )
         end
       end

lib/ruby_llm/providers/openai/images.rb

@@ -20,15 +20,16 @@ def render_image_payload(prompt, model:, size:)
           }
         end
 
-        def parse_image_response(response)
+        def parse_image_response(response, model:)
           data = response.body
           image_data = data['data'].first
 
           Image.new(
             url: image_data['url'],
             mime_type: 'image/png', # DALL-E typically returns PNGs
             revised_prompt: image_data['revised_prompt'],
-            model_id: data['model']
+            model_id: model,
+            data: image_data['b64_json']
           )
         end
       end

spec/fixtures/vcr_cassettes/image_basic_functionality_openai_gpt-image-1_can_paint_images.yml

@@ -33,6 +33,7 @@ def save_and_verify_image(image)
       expect(image.url).to start_with('https://')
       expect(image.mime_type).to include('image')
       expect(image.revised_prompt).to include('cat')
+      expect(image.model_id).to eq('dall-e-3')
 
       save_and_verify_image image
     end
@@ -63,5 +64,16 @@ def save_and_verify_image(image)
         RubyLLM.paint('a cat', model: 'invalid-model')
       end.to raise_error(RubyLLM::ModelNotFoundError)
     end
+
+    it 'openai/gpt-image-1 can paint images' do # rubocop:disable RSpec/MultipleExpectations,RSpec/ExampleLength
+      image = RubyLLM.paint('a siamese cat', model: 'gpt-image-1')
+
+      expect(image.base64?).to be(true)
+      expect(image.data).to be_present
+      expect(image.mime_type).to include('image')
+      expect(image.model_id).to eq('gpt-image-1')
+
+      save_and_verify_image image
+    end
   end
 end