[Feature Request]: Better Groups: They should be selectable and easy to save, duplicate, and move in bundles

### Is there an existing issue for this?

- [X] I have searched the existing issues and checked the recent builds/commits

### What would your feature do ?

Currently groups are unselectable which means they have to be moved one at a time. For big workflows where things are often rearranged this quickly becomes cumbersome to deal with. It also means there's no mechanism by which one can easily duplicate a group. The only way to do so currently is to copy and paste the nodes from the group you want to duplicate, then put the pasted nodes in their own group. This becomes time consuming quickly, and brings us to another point: because groups are unselectable they also cannot be saved as part of a template, meaning any nodes saved in a template must be regrouped upon placing a new instance of the template. All these things culminate to make groups sometimes more hassle than help.

### Proposed workflow

1. Group some nodes together
2. Click the group's title bar to select it (clicking in body of group will be ignored, same as current behavior)
3. Do any number of operations: copy, paste, save as template, select other groups and drag all together, opt+drag to duplicate
4. Bonus: double click the group anywhere inside of it (OTHER than it's title bar) and it will select all nodes in the group.

### Additional information

This would make workflow management so much less of a bear.