Summary:
Improve display of app info in the following ways
- Display the app's caption in bold and apart from the other pieces to make it stand out more
- Group the pieces of info in a recognizable section
- Right-justify all the labels to make everything easier to parse
- Don't display the category with a link color since it's not a link

Test Plan:
Tested in KDE Neon. Before:
{F5577431}

After:
{F5587546}

(Ignore the duplicated categories in the sidebar; that's an unrelated issue tracked by https://bugs.kde.org/show_bug.cgi?id=388313)

Reviewers: apol, #vdg, #discover_software_store

Reviewed By: apol, #discover_software_store

Subscribers: colomar, januz, alexeymin, plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D9542