Renders generic registry post_install guidance + lifecycle requirements in the
Settings extensions gallery card (manifest-driven, no vendor special-casing).
Fixes#4959. Rebased onto current master (squash-applied #4964's net diff so it
coexists with the #4979 sidecar-runtime-status feature that landed in v0.51.697).
Co-authored-by: franksong2702 <franksong2702@users.noreply.github.com>