pikuri-memory 0.0.4

pikuri-memory is a placeholder gem reserving the +pikuri-memory+ name on RubyGems for an upcoming "memories" extension to pikuri — durable long-lived facts about the user and the project that persist across conversations, modeled after the memory concept in https://github.com/nousresearch/hermes-agent. The gem ships no Ruby code yet; this release only claims the name so the eventual extension can publish under it.