dfm_check held a board on an HDI build to JLC's standard-build floors until this fix. Annular ring is now measured only on layers a hole actually crosses. In #618, escape routing for 0.4 and 0.5 mm BGAs on microvia stacks passed kicad-cli DRC with 0 errors, but both PRs say the whole suite wasn't run, and hdi-bga still hits open dfm_check items. Checks are only as good as the fab rules they're told to use.