- FloatingCallWidget: drop !conversation early-return in handleJoinCall —
on a fresh account or after a hard refresh the inbound call's conversation
may not be in the Vuex store yet, which silently no-op'd Accept while
Reject worked (Reject doesn't read the conversation).
- useCallSession: seed the calls store from already-loaded voice_call
messages with status='ringing' on mount and whenever the conversation
list changes. Cable events (voice_call.incoming, message.created) are
one-shot and not replayed on reconnect, so without seeding a refresh
during a ringing call leaves the FloatingCallWidget empty.
- useCallSession: extend the beforeunload warning to fire while a call is
ringing too — losing a ringing inbound to refresh is the same UX hit as
losing an active one.