Heals existing legacy stubs (created when resolveOrCreateReplicatedUser used
homeUserId@domain) by asking the peer for the canonical username via
lookupRemoteUserByHomeId and rewriting the local row. Idempotent and
collision-safe.
Wired into onPeerActivated (per-origin) so future peer flaps re-attempt for
stubs whose home was unreachable on a prior pass, and into a one-shot pass at
startupBootstrapSync for all currently-active peers (not just first-time
lastSyncedAt=0 peers).
Jannis Braun
bdbc90ebd2