Blazor WASM hot reload and debugging

[guardrex]

Fixes #28940

Artak ... This covers the following from the Preview 1 blog post remarks ...

• Hot reload support for instance fields, properties, and events for .NET on WebAssembly
• Support for symbol servers when debugging .NET on WebAssembly
• Blazor WebAssembly debugging in Firefox

... but note that I couldn't find PU PRs for these. I don't have explicit instructions for how to use a symbol server to debug WASM apps outside of our normal VS guidance, so I currently have the PR point to the general guidance at ...

https://learn.microsoft.com/en-us/aspnet/core/test/debug-aspnetcore-source?view=aspnetcore-7.0

Also, don't sweat the version flipping at the top of the debugging article. I'll circle around and clean up the versioning later. I just haven't reached this one yet for a pass on that ... it's coming soon 🏃.

Last item ...... Firefox debugging ..... This will need a clean-up pass, possibly including for if VS can debug with FF using the same approach laid out for Chrome/Edge. I have a tracking item for it to circle back around to this guidance for futher updates later.

Tom, this touches your Hot Reload topic in the main doc set.

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Internal previews

📄 File	🔗 Preview link
aspnetcore/blazor/debug.md	[Visual Studio for Mac](https://review.learn.microsoft.com/en-us/aspnet/core/blazor/debug?branch=pr-en-us-28953)
aspnetcore/test/hot-reload.md	.NET Hot Reload support for ASP.NET Core

[danroth27]

@lambdageek Can you confirm that the list of supported hot reload edits on WebAssembly is accurate? Or are we at the point that hot reload on WebAssembly is at parity with CoreCLR and we no longer need to maintain a separate list of supported edits for .NET 8?

[lambdageek]

@lambdageek Can you confirm that the list of supported hot reload edits on WebAssembly is accurate? Or are we at the point that hot reload on WebAssembly is at parity with CoreCLR and we no longer need to maintain a separate list of supported edits for .NET 8?

We're almost at parity. The remaining things are:

• Renaming method parameter (@fanyang-mono is working on it - [EnC] Implement the UpdateParameters capability runtime#56626)
• The new stuff in .net8p4 isn't quite on par with coreclr (details offline)

[guardrex]

I'll make a tracking note on ...

Renaming method parameter (@fanyang-mono is working on it - dotnet/runtime#56626)

... to check back and update again after that's resolved.

I'll also check back on FF guidance. As it stands, that's a very separate process here during preview. I think the team's goal is to have it be the same process as for Edge/Chrome and not a completely parallel process to use (but I'm not sure). I'll check back on it later.