Feat: Provide option for "Auto" in upload mode

[yash-sangwan]

Is your feature request related to a problem? Please describe.

Currently, users must manually choose between "Multipart Upload" and "Signed URL Upload" methods in the settings. This requires users to understand the technical differences between the two methods and remember to switch based on file size. Users uploading a mix of small and large files need to constantly change this setting, which is frustrating and interrupts their workflow.

Describe the solution you'd like

Add an "Auto" option to the upload method settings that intelligently selects the best upload method based on file size:

• Files < 100MB: Use Signed URL upload (faster, simpler, direct upload)
• Files ≥ 100MB: Use Multipart upload (supports pause/resume, better for large files)

This would be the default option for new users and would provide the best experience without requiring technical knowledge. The auto mode should:

1. Analyze each file size before upload
2. Automatically select the optimal method per file
3. Allow mixed uploads (some files via signed URL, others via multipart in the same batch)
4. Display which method is being used for each file (optional visual indicator)

[huly-for-github]

Connected to Huly®: ODRIV-62