Trigger enhanced page nav on hot reload

[captainsafia]

Depends on dotnet/aspnetcore#50437.

Addresses dotnet/aspnetcore#49144.

Scenario	Validated
Statically server rendered page	✅
Interactive server rendered page	✅
Page with stream rendering enabled	✅
Interactive client rendered page	❌ (dotnet/aspnetcore#50765)
Statically server rendered page with interactive components (all render modes)	✅

[SteveSandersonMS]

From reading Boot.Web.ts in dotnet/aspnetcore, hotReloadApplied is defined as:

  Blazor._internal.hotReloadApplied = () => {
    if (hasProgrammaticEnhancedNavigationHandler()) {
      performProgrammaticEnhancedNavigation(location.href, true);
    }
  };

It looks like that will do nothing if options.ssr.disableDomPreservation is set to true. Do we also need something else to make hot reload work in that case? For example we could add an else block that forces a full-page load.

I appreciate you can't do that in this PR since that's in a different repo. Just check if that's something we need to follow up on today!

[captainsafia]

Opened dotnet/aspnetcore#50790 to follow up.

[SteveSandersonMS]

Looks good! Added a comment about one thing that might need followup but I'm unsure since maybe it's being handled some other way.