Blazor and Razor Pages CRUD scaffolding should visually indicate which fields are required

[MackinnonBuck]

Overview

Currently, when a form gets generated from a model class, there is no visual indication of which form fields are required. The user must first submit the form before getting feedback about which form fields are required.

Proposed fixes

For each form input that gets generated from a model property annotated with a RequiredAttribute, include additional markup to indicate that the field is required. For example:

<div class="mb-3">
+   <span class="text-danger">*</span>
    <label for="title" class="form-label">Title:</label>
    <InputText id="title" @bind-Value="Movie.Title" class="form-control" aria-required="true" />
    <ValidationMessage For="() => Movie.Title" class="text-danger" />
</div>

Before

After

[MackinnonBuck]

Related: dotnet/aspnetcore#56312