The one-line deprecation notice prepended to a deprecated alias’s output.
Stable per tool (no timestamps/counters) so provider-side prompt caching
stays byte-stable (#498).
Initializes the global state from user config (env var > config.toml > default).
Call once during server startup after config is loaded.
If the global was already initialized (e.g. by a concurrent global() call),
applies the categories to the existing state instead.