* fix(ci): exclude check-test-masking.test.ts fixtures from self-referential tautology gate (#6634)
* fix(ci): extend test-masking self-fixture exclusion to sibling gate regression files (#6634)
The #6634 fix added isSelfTestFixtureFile()/scanBareTautologies() exclusions
that only matched check-test-masking.test.ts exactly. Its own new regression
file check-test-masking-selfref-6634.test.ts also embeds tautology-pattern
literals as fixtures/documentation, so the absolute-floor scanBareTautologies
gate self-tripped a HARD failure on the PR's own file. Generalize the
exclusion to the whole check-test-masking* self-test family and lock it with
two regression tests.
ec1e79b8a7