Refactors the old AngleDisplay code-behind into a clean MVVM implementation
with AngleDisplayViewModel (PSG/INJ/Manual encoder angles, zero references,
lock angle calculation with tolerance color coding) and a pure XAML view.
Wires LockAngleFaseReady and PsgModeFaseReady test phase events.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>