The install blocks still asked for hy-memory 2.0.3 (and 2.0.1 extras),
MemHub 1.0.3 (build 7), and said memhub-cli was unpublished. pyproject.toml
ships 2.0.4, the MemHub workspace ships 1.0.4 (build 13), and README already
announces memhub-cli 1.0.5.
Update the install commands and the release metadata in the root READMEs,
the usage/search guides, the monorepo policy, and the MemHub docs. Historical
CHANGELOG entries are deliberately unchanged.
Co-authored-by: qiye.sjh <shijiahao_0802@youzan.com>