feature request: customizable formatters #818

I know there are the experimental hooks, and then the built in formatters, but what if someone wants to use a formatter other than the standard?

Example: at my previous company we wrote a lot of Go and used gofumpt instead of gofmt. So it may be nice to have the option to override the formatter for Go (and other langs).

I also saw a PR for Kotlin formatting that has the same type of thing going on: #612.

Maybe the intention here is to use hooks for other formatters that aren't out of the box supported by opencode but I feel like it could lend itself to being weird if an edit to a file triggered multiple different formatters at the same time which could have unexpected results.

So proposal:

Ability to specify / override formatters in opencode config.

Also as always, if this seems reasonable I am more than happy to open a PR.