make `transform.position`'s `encoder` field context-sensitive

[goldenstein64]

Concerning a P.S. of #1

Additionally, the encoding could be set automatically by listen.handlers.initialize [...], although this would probably mean redirecting the processing to another module since capabilities need to be accessed in a safe way.

[goldenstein64]

The biggest issue I have with implementing this feature is making sure the user is aware that this is happening. This is so the user doesn't duplicate work by accident, and they can implement their own logic as a workaround or extra feature.

[goldenstein64]

Since this issue was filed, transform.position's encoder field is set to UTF-16 on initialization, and it doesn't do anything else about it. I'm still not happy about how you have to travel through 3 sub-directories to find this.

I'm currently thinking of adding a function to lsp that reads server capabilities and changes buried settings like this so the user doesn't have to worry about it as much.