[FEATURE REQUEST] Pre-install 'hook'

[tushev]

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

A section in settings:

• Checkbox: Enable pre-install hook
• Label: A command to execute before installation of each package"
• Text field: Path to executable + parameters
• Checkbox: Do not proceed with package installation if command's exit code is different from 0
• Description of variables that end-user can use inside text field:
  • $PackagePath: Path to newly downloaded package
  • $PackageID: ID of the Package
  • $InstallSystemType: winget/pip/scoop/etc
  • $NewVersion
  • $OldVersion

Describe how this new feature could help users.

This feature will allow advanced users to implement complex custom scenarios without having to request features from UnigetUI:

• custom malware scan before installation
• backing up packages to remote storage
• sending notifications
• custom logging
• handling restart of service Y if package X updates
• delaying updates for certain packages when required (i.e., via in-house API)
• etc, etc