Add support fvm to manage the flutter version

[beastoin]

https://fvm.app/

the initial ideas #2490 #2488 / thank to 0xrushi

reverted, since my concern is that it adds one more step to the current app > setup flow and devs need to use $fvm prefix.

CLI is my main workflow, but i know some great Flutter developers still use the UI.

we need to compare it with the simple $git checkout <version> - everything should work well for both CLI and UI.

[thisisamank]

Hey @beastoin, I am first time contributing to omi. UI would use flutter sdk location of the IDE, so if the developers set the path to fvm, the UI would automatically pick up fvm's managed flutter version and that would remove the use for fvm prefix. I can raise a PR by adding fvm in script.sh and setting the default version of flutter to 3.24.1. Please assign me if this is what we wanted.