D5 cleanup, frontend and backend in one commit: removes the six
config_validate::* statuses that never receive a backend send and the
set_config::ok send (enum variants, golden list 41→34, send point in
restart_clash_core), their frontend handlers, and the five i18n keys only
those handlers used. The notice table is now typed as a Record over the
generated NoticeStatus union, so a status without a frontend entry fails
to compile. The info status (sent by the silent updater for breaking
change notices, previously dropped with a console warning) now shows an
info toast — the one deliberate behavior delta.
Tunglies