[FEATURE REQUEST] Thumbnail view of the package to be installed

### 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 proposal is a completely new feature. If you want to suggest an improvement or an enhancement, please use [this template](https://github.com/Devolutions/UniGetUI/issues/new?labels=enhancement&projects=&template=enhancement-improvement.yml&title=%5BENHANCEMENT%5D+%28Enter+your+description+here%29).

### Describe the new feature

UniGetUi does not currently have a feature to display thumbnails of the packages to be installed; this is important because an image can give a more general idea of ​​the software to be installed.

### Describe how this new feature could help users

When selecting a package, right-clicking and choosing "Package Details" from the UniGetUI pop-up menu displays a window with package details, including one or more software thumbnails.

I propose keeping this functionality, but also opening a banner below the packages with general details of the software to be installed, including one or more thumbnails, when a package is selected. If no package is selected, this banner should be hidden.

I've attached a couple of screenshots: the first shows the current view of UniGetUI, and the second shows how this feature could be implemented.

Inizia selezionando un pacchetto e aprendo la vista esistente "Package Details" per capire come vengono attualmente presentati i dettagli dei pacchetti e le miniature. Poi segui l’UI di selezione dei pacchetti e determina come un banner sotto l’elenco dei pacchetti potrebbe mostrare gli stessi dettagli e nascondersi quando non è selezionato nulla; il lavoro è completato quando il banner mostra i dettagli e le miniature del software richiesto solo per il pacchetto selezionato.

Scritto dal modello di indicizzazione a partire dal testo della issue.