Search in project root uses `$(cmd)` which isn't compatible with fish shell

[rlivings39]

#42 added some highly requested features. However it relies on $(cmd) for command substitution. Fish shell users (like me) hit errors because the syntax for fish is (cmd). Making an issue to sort this out. Maybe we can just check the terminal settings to craft the right command?

[clearfeld]

Maybe we can just check the terminal settings to craft the right command?

Sure, I could add a $SHELL --version check if the system isn't windows, and then determine whether to use the standard $() substitution or use a different one depending on the shell and version. I've taken a look at the fish shell and it seems from fish shell v3.4.0 it supports the standard $() substitution syntax. So maybe just for fish shells < 3.4.0 we could use the alternative syntax. If this seems like a good approach / solution let me know and I'll make a PR for it.