fix(backend): Implement passed uploaded media support for AI image customizer block (#11441)

- Added `store_media_file` utility to convert local file paths to Data
URIs for image processing.
- Updated `AIImageCustomizerBlock` to utilize processed images in model
execution, improving compatibility with Replicate API.
- Added optional Aspect ratio input to AIImageCustomizerBlock

This change enhances the image handling capabilities of the AI image
customizer, ensuring that images are properly formatted for external
processing.

<!-- Clearly explain the need for these changes: -->

### Changes 🏗️

<!-- Concisely describe all of the changes made in this pull request:
-->

### Checklist 📋

#### For code changes:
- [x] I have clearly listed my changes in the PR description
- [x] I have made a test plan
- [x] I have tested my changes according to the test plan:
  <!-- Put your test plan here: -->
- [x] Created agent using AI Image Customizer block attached to agent
file input
  - [x] Run agent, confirmed block is working
- [x] Confirm block is still working in original direct file upload
setup.


### Testing Results

#### Before (dev cloud):
<img width="836" height="592" alt="image"
src="https://github.com/user-attachments/assets/88c75668-c5c9-44bb-bec5-6554088a0cb7"
/>


#### After (local):
<img width="827" height="587" alt="image"
src="https://github.com/user-attachments/assets/04fea431-70a5-4173-bc84-d354c03d7174"
/>

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Preprocesses input images to data URIs and adds an `aspect_ratio`
option, wiring both through to Replicate in `AIImageCustomizerBlock`.
> 
> - **Backend**
>   - **`backend/blocks/ai_image_customizer.py`**:
> - Preprocesses input images via `store_media_file(...,
return_content=True)` to Data URIs before invoking Replicate.
> - Adds `AspectRatio` enum and `aspect_ratio` input; passed through
`run_model` and included in Replicate input.
>     - Updates block test input accordingly.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
4116cf80d7. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

---------

Co-authored-by: Zamil Majdy <zamil.majdy@agpt.co>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Nicholas Tindle <nicholas.tindle@agpt.co>

autogpt_platform/backend/backend/blocks/ai_image_customizer.py

@@ -1,3 +1,4 @@
+import asyncio
 from enum import Enum
 from typing import Literal
 
@@ -19,7 +20,7 @@ from backend.data.model import (
     SchemaField,
 )
 from backend.integrations.providers import ProviderName
-from backend.util.file import MediaFileType
+from backend.util.file import MediaFileType, store_media_file
 
 
 class GeminiImageModel(str, Enum):
@@ -27,6 +28,20 @@ class GeminiImageModel(str, Enum):
     NANO_BANANA_PRO = "google/nano-banana-pro"
 
 
+class AspectRatio(str, Enum):
+    MATCH_INPUT_IMAGE = "match_input_image"
+    ASPECT_1_1 = "1:1"
+    ASPECT_2_3 = "2:3"
+    ASPECT_3_2 = "3:2"
+    ASPECT_3_4 = "3:4"
+    ASPECT_4_3 = "4:3"
+    ASPECT_4_5 = "4:5"
+    ASPECT_5_4 = "5:4"
+    ASPECT_9_16 = "9:16"
+    ASPECT_16_9 = "16:9"
+    ASPECT_21_9 = "21:9"
+
+
 class OutputFormat(str, Enum):
     JPG = "jpg"
     PNG = "png"
@@ -69,6 +84,11 @@ class AIImageCustomizerBlock(Block):
             default=[],
             title="Input Images",
         )
+        aspect_ratio: AspectRatio = SchemaField(
+            description="Aspect ratio of the generated image",
+            default=AspectRatio.MATCH_INPUT_IMAGE,
+            title="Aspect Ratio",
+        )
         output_format: OutputFormat = SchemaField(
             description="Format of the output image",
             default=OutputFormat.PNG,
@@ -92,6 +112,7 @@ class AIImageCustomizerBlock(Block):
                 "prompt": "Make the scene more vibrant and colorful",
                 "model": GeminiImageModel.NANO_BANANA,
                 "images": [],
+                "aspect_ratio": AspectRatio.MATCH_INPUT_IMAGE,
                 "output_format": OutputFormat.JPG,
                 "credentials": TEST_CREDENTIALS_INPUT,
             },
@@ -116,11 +137,25 @@ class AIImageCustomizerBlock(Block):
         **kwargs,
     ) -> BlockOutput:
         try:
+            # Convert local file paths to Data URIs (base64) so Replicate can access them
+            processed_images = await asyncio.gather(
+                *(
+                    store_media_file(
+                        graph_exec_id=graph_exec_id,
+                        file=img,
+                        user_id=user_id,
+                        return_content=True,
+                    )
+                    for img in input_data.images
+                )
+            )
+
             result = await self.run_model(
                 api_key=credentials.api_key,
                 model_name=input_data.model.value,
                 prompt=input_data.prompt,
-                images=input_data.images,
+                images=processed_images,
+                aspect_ratio=input_data.aspect_ratio.value,
                 output_format=input_data.output_format.value,
             )
             yield "image_url", result
@@ -133,12 +168,14 @@ class AIImageCustomizerBlock(Block):
         model_name: str,
         prompt: str,
         images: list[MediaFileType],
+        aspect_ratio: str,
         output_format: str,
     ) -> MediaFileType:
         client = ReplicateClient(api_token=api_key.get_secret_value())
 
         input_params: dict = {
             "prompt": prompt,
+            "aspect_ratio": aspect_ratio,
             "output_format": output_format,
         }