I hope you are doing well.
Since the current feature request was implemented in the previous version of the welkin Suite IDE, I'll be happy to close this topic as Implemented.
Here you can find all the information on how to add your existing SOQL queries and Anonymous Apex files to your new project.
More than that, you can add other existing files, like apex classes, objects, triggers, etc., to your new project, moving them to an appropriate subfolder in the project folder -> src and using the 'Refresh project according to sources' command from the menu Project. Please find more info on this here.
Hope this brings a little pleasure to your working process.
If you have any questions on these on any other functions in the IDE, please let us know.
Have a nice day!