chore: More internal stsn exports

[pan-kot]

A follow-up for #155.

We need more exports to replace the STSN utils from components with the toolkit version:

1. The renderWithSingleTabStopNavigation util used in multiple subscribed components tests
2. The SingleTabStopNavigationContext and defaultValue used for modal context reset. Instead of exposing these two I created a dedicated SingleTabStopNavigationReset component.

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 99.42%. Comparing base (2916206) to head (ef508dd).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #156   +/-   ##
=======================================
  Coverage   99.42%   99.42%           
=======================================
  Files          35       35           
  Lines         864      866    +2     
  Branches      245      247    +2     
=======================================
+ Hits          859      861    +2     
  Misses          5        5           

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