Check lru_cache usage in v4

HA has a great service for analyzing lru use in https://www.home-assistant.io/integrations/profiler/#action-lru-stats Once this merges and we have a backported version I can run it on a live system and we can do a followup to tweak it based on how it shows in real world usage. _Originally posted by @bdraco in https://github.com/aio-libs/aiohttp/pull/10890#discussion_r3406884408_ Need to wait till we have a new pre-release of v4.