[Blazor] Use <LinkPreload /> component to preload assets

[maraf]

Using link headers has several disadvantages

• It's complicated to correct identify root without doing per request processing
• It's more indirect when people want to turn the feature off

For these reasons we have decided to switch to a component-based approach. Thanks to <base href="https://github.com/..."> element, preload links are correctly rooted.
This PR adds <LinkPreload /> component that in case of InteractiveWebAssembly component presence on the page generates preloading links into the place where the component is used, into the HTML head, after the <base href="https://github.com/...">. In case there isn't any InteractiveWebAssembly, the component does nothing.

This PR also updates the BlazorWeb template to include the <LinkPreload /> component.

Fixes #62174

[javiercn]

Looks great!

[dotnet-policy-service]

@@maraf, this change will be considered for inclusion in the blog post for the release it'll ship in. Nice work!

Please ensure that the original comment in this thread contains a clear explanation of what the change does, why it's important (what problem does it solve?), and, if relevant, include things like code samples and/or performance numbers.

This content may not be exactly what goes into the blog post, but it will help the team putting together the announcement.

Thanks!