notes003

2. Lock Down the Assignment Flow (In Practice) Add this to your README or CONTRIBUTING.md:

Never assign to GlobalVariables.err directly in XAML or Invoke Code.

Use GlobalErrorHelpers.Set(...) only.

Access with GetOrCreate() or TryGet().

Enforce in README / CONTRIBUTING.md:

markdown Copy Edit Do not reference GlobalVariables.err directly in Assign or Condition expressions.
Always use GlobalErrorHelpers.GetOrCreate() or HasError().