[Blazor] Disable enhanced navigation on a per-element basis

[javiercn]

• Check for a data-enhanced-navigation attribute on the element.
• Skip using enhanced navigation if that's the case and fallback to a traditional reload.

[mkArtakMSFT]

We should also consider enabling a scenario for disabling enhanced navigation for a component hierarchy, rather than a single component only.

[SteveSandersonMS]

Done in #50551

The new rules are:

• For forms, enhanced nav is off by default. To turn it on, put data-enhance on the form element, or Enhance if it's an EditForm
• For links, enhanced nav is on by default. Control it by putting data-enhance-nav="true/false" either on the <a> itself or on any ancestor element. When a link is clicked, we find its closest ancestor with a setting and use that, so you can override in either direction.