check-skill-counts

Verify that README skill counts match the actual number of SKILL.md files in the filesystem. Use when (1) before creating a pull request or release to ensure documentation accuracy, (2) after adding or removing skills from any plugin, (3) repository health verification or documentation consistency checks are requested, (4) during README updates to confirm new numbers are correct, (5) as part of comprehensive validation alongside check-versions and check-changelogs, (6) when marketplace listing seems inconsistent with actual plugin contents.