Rianfowler/sc 58965/adding typechecking to top level routes routes view files

[rianfowler]

What this PR does / why we need it:

• adds typechecking to KotsApplicationTree

Which issue(s) this PR fixes:

https://app.shortcut.com/replicated/story/58965/adding-typechecking-to-top-level-routes-routes-in-the-navbar

Special notes for your reviewer:

Steps to reproduce

Does this PR introduce a user-facing change?

NONE- refactor

Does this PR require documentation?

NONE