Detect stale Codex app-server catalogs

[theFong]

Summary

• avoid rewriting an unchanged combined model catalog
• track material catalog/provider changes and detect whether a running Codex app-server is stale
• print the correct restart and Desktop reconnect order for managed and legacy unmanaged daemons
• preserve read-only behavior for --check and suppress notices after a newer daemon has loaded the files

Validation

• ./test.sh
• bash -n install.sh codex-setup.sh test.sh
• shellcheck codex-setup.sh
• git diff --check
• actionlint .github/workflows/bootstrap.yml