Fix file sharing load speed and move error; misc updates

- Remove recursive directory size calculations (single Seafile API call per list)
- Remove 'Used in this location' usage display
- Fix move using v2 per-type endpoints instead of broken batch endpoint
- Send entry type from frontend for correct move routing

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

supabase/migrations/20260423113000_allow_client_revision_unassign.sql

@@ -0,0 +1,30 @@
+-- Allow client revision returns to clear stale assignments while keeping
+-- assignment fields protected for normal client updates.
+create or replace function public.guard_task_update()
+returns trigger as $$
+declare
+  caller_role text;
+begin
+  select role into caller_role from public.profiles where id = auth.uid();
+
+  if caller_role = 'client' then
+    new.project_id := old.project_id;
+    new.invoiced := old.invoiced;
+
+    if not (
+      new.status = 'not_started'
+      and coalesce(new.current_version, 0) > coalesce(old.current_version, 0)
+      and new.assigned_to is null
+      and new.assigned_name is null
+    ) then
+      new.assigned_to := old.assigned_to;
+      new.assigned_name := old.assigned_name;
+    end if;
+  elsif caller_role = 'external' then
+    new.project_id := old.project_id;
+    new.invoiced := old.invoiced;
+  end if;
+
+  return new;
+end;
+$$ language plpgsql security definer;