<!-- CURSOR_SUMMARY -->
> [!NOTE]
> - **Image attachments handling:** In `prepareMessageWithAttachments`,
images are now read, converted to base64, and included as `image`
(base64) with `mediaType` instead of raw Buffers, ensuring proper JSON
serialization for `aiMessagesJson`.
> - **Storage limit increase:** `MAX_AI_MESSAGES_SIZE` raised from 1MB
to 10MB in `ai_messages_utils.ts` to accommodate larger serialized
message payloads.
> 
> <sup>Written by [Cursor
Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit
b81483775dc7e6535c7396f417818eb638003248. This will update automatically
on new commits. Configure
[here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

<!-- This is an auto-generated description by cubic. -->
## Summary by cubic
Fixes image attachments by storing images as base64 with a mediaType so
they serialize to JSON correctly. Also increases ai_messages_json size
limit to 10MB to prevent save failures.

- **Bug Fixes**
- Store .jpg, .jpeg, .png, .gif, .webp as base64 and set mediaType
(e.g., image/jpeg, image/png) for safe JSON serialization.
  - Raise MAX_AI_MESSAGES_SIZE from 1MB to 10MB.

<sup>Written for commit b81483775dc7e6535c7396f417818eb638003248.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->