Create native SPA UI for the new Indentity API in Dotnet 8

[kjartanvalur]

Problem Statement:
In numerous scenarios, complete control over the login and identity management process is crucial. Integrating this functionality directly within the Single Page Application (SPA) is often the most effective approach, ensuring seamless user experience and greater control.

Proposed Solution:
Develop a robust UI, either in Angular or React, to replace all existing Identity razor pages. This new interface will utilize the advanced Identity Endpoints introduced in Dotnet 8, ensuring a more integrated and streamlined identity management process within the SPA.

Considered Alternatives:
Alternatives explored include leveraging third-party solutions such as Azure Entra (B2C) or Auth0. However, the proposed solution offers a more integrated and cohesive approach, aligning closely with the principles of Clean Architecture and the goals of the template.