Replaces the shared IsBusy/IsMerging flags in WorktreesOverviewModalViewModel and the
reset flow in WorktreesSettingsTabViewModel with dedicated OperationStatus instances
shown via OperationIndicator, so a running Refresh no longer blocks the Cleanup
indicator. ForceRemove gains a CanExecute guard against re-entrancy while it's running,
and the reconcile tick's busy guard now checks all four action statuses instead of the
old IsBusy||IsMerging pair.
TryInvokeAsync catches every exception and returns null, which is fine
for read-only calls but hid real HubException reasons behind a generic
"offline" message for the 7 mutating call sites (RestoreDefaultAgents,
UpsertPrimeSchedule, AddDailyNote, CleanupFinishedWorktrees,
ResetAllWorktrees, ForceRemoveWorktree, BuildPlanningIntegrationBranch)
— the same bug class fixed for ApproveReview in e1807fd. Each of the 22
TryInvokeAsync call sites was audited; the 15 read-only ones are left
unchanged (empty/offline is the right display). For the 7 switched to
a direct hub invoke, every caller was checked and, where it had no
catch, one was added so the exception surfaces (StatusMessage,
ShowErrorAsync/CombinedWarning) instead of crashing.
Mika Kuns