feat(dataset): import dataset at specific tags

[m-alisafaee]

Description

Allows specifying a dataset tag when importing a Renku dataset. It then imports the specified version (files and metadata) instead of the latest version.

Fixes #2904
Fixes #2910

[Panaetius]

Thank you for removing attrs!

I think the whole dataset add/import logic has grown a bit organically over the years, and it's become a bit hard to follow in parts, with many edge cases and different conditions. I wonder if at some point we should refactor it, with dedicated classes for different behaviors. Similar to how we reworked the template logic.
That might make it easier to understand and maintain.

[m-alisafaee]

I think the whole dataset add/import logic has grown a bit organically over the years, and it's become a bit hard to follow in parts, with many edge cases and different conditions. I wonder if at some point we should refactor it, with dedicated classes for different behaviors. Similar to how we reworked the template logic. That might make it easier to understand and maintain.

Totally agreed! I believe a good time for this is when we want to implement new dataset features like adding pointers from S3.

[Panaetius]

Thank you