Strategies, pre-call checks, cooldown and fallback helpers, and the auto, complexity and quality
sub-routers now take a RoutingContext instead of the Router, and read the router only through
registry(), settings(), health() and the context's forwarding methods. Router-free helpers move
from router_utils to litellm_core_utils, outside callers of router state switch to entry points,
and the surface allowlist shrinks to the endpoint methods plus the entry points