fix(test-runner): self-contain project registration

[mPokornyETM]

Summary

• remove the shared test runner action's dependency on a sibling action directory
• register TfCustomizedSquirt directly through the public npm package
• keep the existing test-runner and PVSS log handling flow intact

Validation

• validated actions/winccoa-ctrl-test-framework-runner/action.yml with workspace diagnostics

Why

• remote action consumers only get the requested action directory checked out under _actions
• resolving ../winccoa-register-project/scripts/run.sh therefore still failed even after fixing the old nested local uses syntax