fix(editor): should update image size field (#12274)

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->
## Summary by CodeRabbit

- **New Features**
  - Image content now includes file size information in its metadata.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

blocksuite/affine/shared/src/adapters/image.ts

@@ -101,6 +101,7 @@ export class ImageAdapter extends BaseAdapter<Image> {
         flavour: 'affine:image',
         id: nanoid(),
         props: {
+          size: item.size,
           sourceId: blobId,
         },
         children: [],