Add self-update command

[dominosaurs]

Description

Currently, to update phpvm to the latest version, users have to manually pull the latest changes or rerun the installation script. Adding a built-in self-update command would streamline this process and ensure users are always running the latest stable release with minimal friction.

Feature Details

Just a simple self-update command, and will print the latest version when it finished. Example:

$ phpvm self-update
Updating phpvm...
phpvm successfully updated to the latest version: v1.12.0.

$ phpvm self-update
You are already on the latest version: v1.12.0.

Additional Information

N/A

[Thavarshan]

Hi @dominosaurs, thanks for bringing this up! I'll see if I can get this done by myself but any help is appreciated as I'm a bit too occupied these days.

[dominosaurs]

first of all, thanks for your incredible work, i really love it.

honestly i want to directly create a pull request but i overthink is this feature is aligned with your vision for this project. thats why i open the issue/feature request first. anyway i am so excited with the #19 🎉.

[Thavarshan]

This is actually a genuinely brilliant idea @dominosaurs!