Port legacy MVC views to Blazor components for the receiver UI, including Home, envelope routing, locked/auth flows, document signing, signature pad dialog, and all terminal/confirmation pages (signed, rejected, expired, not found, 404).
Implements DevExpress Blazor controls for UI consistency and accessibility.
Signature flow uses a side-panel UX for capturing signatures.
Includes localization, robust error handling, state management, and JS interop for signature capture and 404 animation.
Legacy routes are redirected for backward compatibility.
