emitWorkspaceUpdateForCwd and emitWorkspaceUpdatesForCwds blocked on
reconcileActiveWorkspaceRecords() (stat + reconcile on every active
workspace) before pushing the target workspace update to clients. This
caused new worktrees to appear in the sidebar with a noticeable delay
after the agent was already visible.
Emit the target workspace immediately from the registry snapshot, then
run reconciliation in the background via reconcileAndEmitWorkspaceUpdates.
Ensure the dedupeGitState early-return still triggers background
reconciliation so metadata changes (branch renames, display names)
are not silently dropped.