add test/ dir to templates

[nick1udwig]

Problem

Resolves #98

Solution

Add a test/ dir to templates, inspired by forge.

Docs Update

TODO

Notes

Getting all the versions to align is getting increasingly painful. Not sure if this is because I'm less on-top of all the changes that are happening or if there really are more things to coordinate. Regardless, this is a big pain point and we should figure out if there is a way to make this easier for devs.

[nick1udwig]

Although this needs a docs update AND only adds a test/ dir for rust chat AND needs some slight additional work on kit run-tests to work just pointing at the package dir -- I'm merging this to fix templates which have mismatched versions on develop.