e2e-fixture-skilllisted

# E2E Fixture Skill <!-- Regression fixture for AGENTS.md's "Integration test" section. The generic `name:` and deliberately vague `description:` above are load-bearing: they keep the triggering baseline well below 1.0 (verified: single-model, single-repeat baseline mean_accuracy ~0.5-0.65, 0% recall on the should_trigger=true queries), which is what forces Gate 3's optimize loop to actually call the improver instead of exiting at iteration 0 on a saturated score. Do not "fix" this description or rename this skill to something more descriptive -- that would silently defeat the fixture's purpose and the next agent to run Gate 3 would get a false pass (no improver artifacts) without any error. --> Break down a regular expression into its component parts and explain what each part matches. Use this when a user has a regex that isn't behaving as expected, or wants to understand/document an existing pattern.