Launcher - Add alias support

[thnk2wn]

Summary of the new feature/enhancement

I'd love to be able to setup aliases where a user-meaningful short keyword can be mapped to an app, file, or URL (with parameters / arguments optional).

This would be similar in ways to "magic words" in the old SlickRun (https://bayden.com/SlickRun/1033/SlickRunHelp.aspx).

Typing the keyword would autocomplete and opening / selecting / invoking would launch the corresponding file / app / url.

Proposed technical implementation details (optional)

A "..." button could appear near search icon to launch a config screen or open a config file. There might also be a syntax or keyword to configure these aliases (like "setup" in SlickRun).

[enricogior]

Closing in favor of the more general custom commands feature #3600