[FR]: Gazelle: Generate different types of targets for tests vs sources

[mrmeku]

What is the current behavior?

Right now both tests and source targets are generated as ts_projects. This is fine in principle as a default, but disallows me to generate a different kind of target for my tests since both have the same kind so gazelle's map_kind directive applies to both tests and source targets.

Describe the feature

Tests target should have a different kind (in gazelle terms) than source targets. If this were the case, I could independently configure the kind of my source files to be my own fe_library rule and have my tests be my own my_special_test rule.

[Aghassi]

My company would benefit from support for this. We currently have patched the gazelle plugin to enable this internally