[PB-6474] bugfix/Photos fixes and improvements

[CandelR]

Summary

• iOS video thumbnails: Videos in the Photos Library are only accessible for thumbnail generation via PHAsset URI (ph://). Direct /var/mobile/Media/DCIM/ paths fail with NSCocoaErrorDomain 257. Fixed by returning thumbnailUri (the ph:// asset URI) from resolveLocalPath and patching react-native-create-thumbnail to handle ph:// via PHImageManager.
• Cloud-only 404 on playback: PhotoAssetFetchService was using user.bucket (Drive root) instead of asset.bucket (Photos bucket) when downloading cloud-only assets.
• Duplicate device folders: ensureDeviceFolder could be called concurrently during app startup, causing the backend created duplicate device folders. Fixed with a pending-promise mutex in PhotoDeviceManagerService.
• Orphaned device assets in timeline: Assets from deleted devices persisted in local cloud_asset DB indefinitely. syncAllHistory now calls purgeDeletedDevices at the start of each sync cycle.
• Upload order: oldest assets uploaded first. Changed to ORDER BY creation_time DESC NULLS LAST so recent assets upload first.
• Video indicator for cloud-only assets: CloudPhotoCell now shows a play icon badge via the new shared VideoBadge.
• toFileUri updated to pass through any existing URI scheme (://), not just file://.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud