Add a “Destination” field to the Upload Object modal in the UI

[Annaseli]

What

1. Add a "Destination" field to the Upload Object modal in the UI.
2. Optionally, display only the uploaded file name(s) beneath the "X File(s) to upload" field.

Why

There’s a clarity gap in the Upload Object modal. After filling in the Path field, it’s not clear where the file will actually be uploaded in lakeFS.

Specifically:

• The distinction between a lakeFS object URI (e.g., lakefs://repo/main/my/dataset) and a lakeFS path (e.g., my/dataset) isn't clearly communicated.
• It's unclear what the upload root is, and how the Path field is interpreted (e.g., does it get concatenated to lakefs://repo/main/?).
• Trailing slashes in file names can lead to confusing results, since lakeFS doesn’t support actual directories and doesn’t support move operations of objects — so uploading to the wrong path requires deletion and re-upload.

This ambiguity can lead to user errors or unexpected behavior.

Suggested Solution - by Tal

Inspired from S3's behavior:

• Add a "Destination" field in the Upload Object modal to explicitly show the final target destination.
• Displaying the uploaded file name(s) can also improve clarity.

This gives users clear visibility into where their object will be uploaded and what objects will be uploaded before confirming. In my opinion, this would make the upload process more transparent, reduce confusion, and improve the user experience.