[FEATURE REQUEST] Add shortcut to install missing package managers

[karpuzikov]

Please confirm these before moving forward.

• I have searched for my feature proposal and have not found a work-in-progress/duplicate/resolved/discarded issue.
• This proposal is a completely new feature. If you want to suggest an improvement or an enhancement, please use this template.

Describe the new feature

Currently is any package manager is not installed there is a message "You may need to install Scoop in order to use it with UniGetUI."
It would be great to have something like "Install ____ package manger" button, that will activate installation command for ex "winget install -e --id pnpm.pnpm"
Or open download page in browser.

Describe how this new feature could help users

That will save time for searching and installing package managers manually