[IMPROVEMENT] Move download/install queue to a seperate tab

### Please confirm these before moving forward.

- [x] I have searched for my feature proposal and have not found a work-in-progress/duplicate/resolved/discarded issue.
- [x] This improvement refers to an existing feature. If you want to suggest a new feature, please use [this template](https://github.com/marticliment/WingetUI/issues/new?assignees=marticliment&labels=new-feature&projects=&template=feature-request.yml&title=%5BFEATURE+REQUEST%5D+%28Enter+your+description+here%29).
- [x] This improvement is not a bug. If you want to report a bug, please use [this template](https://github.com/marticliment/WingetUI/issues/new?assignees=marticliment&labels=bug&projects=&template=bug-issue.yml&title=%5BBUG%5D+%28Enter+your+description+here%29).

### Describe the improvement

Right now, downloads/installs/updates are all shunted into a split view below the usual interface in the Software Updates tab.

From a functionality perspective, this makes little sense, given that there is a feature to batch update apps so there is often no ongoing need to continue interacting with this page after initially choosing to update the apps you've selected.

From a UX perspective this is an absolute nightmare, it's very difficult to monitor/manage ongoing updates and downloads when they're all crammed into a tiny segment at the bottom of a page, where the top half is consumed (again) by features that I don't currently need to use. See what I mean here, with ~60 pending updates I have to scroll for ages to find specific programs to manage. It's visually very cluttered and an uncomfortable user experience:

My proposal is a simple fix; just move the queue to its own tab.

### Describe how this improvement could help users

As above; managing queued downloads would become a much clearer & cleaner experience and it wouldn't mess with any existing functionality.