X_CONFIG_KEY_READER_AMBIGUOUS

an AppConfig leaf key's only "readers" are files matching its bare name, none of them in the section's own package and none spelling the qualified <section>.<key>

X_CONFIG_KEY_UNREAD matches a bare property access on purpose — a package takes CacheConfig as a parameter and reads cfg.driver — and that looseness is itself an instance of the defect it hunts. realtime.tier was read by nothing and NINETEEN files matched the bare tier, packages/policy/src/surfaces.ts on the words tier, in its own file header, so the rule built to catch a dead key reported ✓ over one. Nineteen readers should always have been the alarm

read the key through its section in its owning package so the qualified path appears in source, or delete it from packages/core/src/config.ts and from defaults(); to keep it deliberately, add it to CONFIG_AMBIGUOUS_PINS in scripts/lib/config-reader-pins.ts with the sentence naming the reader