verifying-change-coverage

Verifies that the lines and branches a change actually touched are executed by tests, using LCOV or Cobertura diff coverage instead of whole-repo percentages, and escalates uncovered high-risk changes into a blocking finding. Use when a pull request needs a coverage gate that unrelated tests cannot satisfy, when total coverage looks healthy but the diff is untested, when wiring diff coverage into CI, or when someone claims a change is covered because the suite is green.