CoalTipple v1.0.16

Routing-safety hardening + a routing-savings benchmark.

• mergeKeywordGroups — a config keyword group now inherits the base group's flags and UNIONs its words (deduped), so a custom override can never silently drop a built-in sensitive word or flag (hardens the never-delegate-down gate).
• validateRanking — rejects a ranking where no routable tier holds a usable model (a local-only / empty-model ranking that reads green but routes to nothing).
• Routing-savings benchmark — main does it itself vs delegates to a cheap worker: ~70-75% cheaper to delegate a big mechanical task above the delegateMinLines floor (sensitive work is never delegated down). Recorded in the series benchmarks; the README links it.

Propagate: claude plugin update coaltipple@coaltipple then restart.