Development record

`.abcd/development/brief/05-internals/03-configuration.md:150` says the `force_refresh_every_n` counter only re-injects always-relevant domains. At the backstop `Inject` clears the whole ledger and the recalled ledger, so every domain the prompt matches comes back, and `RuleSet.Match` (`internal/core/rules/rules.go:648`) injects nothing the prompt does not name or hit, so a domain that never recall-matches is not injected at all. The comments at `internal/core/rules/inject.go:56`, `internal/core/rules/inject.go:147` and `internal/core/rules/inject.go:455` carry the same wording.