The 'pql decisions coverage' subcommand was removed in pql 1.4.x — the replacement is the 'coverage_gaps' field on 'pql plan status'. No production callers used this IPC surface; only the unit test referenced it. Removes the IPC registration, the PqlClient helper, and the matching test case. Net negative LOC. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>