feat: Use package installer of choice instead of the system's one

[madkarmaa]

Feature description

The manager currently uses the system's package installer (com.google.android.packageinstaller) when installing a patched app by opening an install session.

The code should launch an intent to open the .apk file rather than opening an install session, so that the end user can choose which package installer to use, as long as it doesn't prevent detecting if the package has been installed successfully or not (for logging verbosity towards the end user), in which case it's fine to leave everything as-is and close this issue.

Motivation

While using the system's package installer is fine in most cases, there are more advanced users who could be using different applications capable of installing packages, such as InstallerX Revived (which has many customizable installation options).

Acknowledgements

• I have checked all open and closed feature requests and this is not a duplicate.
• I have chosen an appropriate title.
• All requested information has been provided properly.