Add event dispatch middleware logging to Blazor Server

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Add event dispatch middleware logging to Blazor Server

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Add event dispatch logging to Blazor Server for parity with WebAssembly

Description

Blazor Server was missing event dispatch logging that WebAssembly already had via addDispatchEventMiddleware. This adds visibility into user interactions alongside existing render batch logging.

Changes:

• Import addDispatchEventMiddleware from WebRendererInteropMethods in Boot.Server.Common.ts
• Register middleware in startServerCore to log event handler ID at Debug level

addDispatchEventMiddleware((_browserRendererId, eventHandlerId, continuation) => {
  logger.log(LogLevel.Debug, `Dispatching event with handler id ${eventHandlerId}.`);
  continuation();
});

Fixes #45674

Original prompt

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This section details on the original issue you should resolve

<issue_title>[Blazor] Blazor Server/Webassembly should call setEventDispatcherMiddleware to wrap event dispatching and capture logs</issue_title>
<issue_description>Our logging on the client should not just include when the render batches happen, but also when the user interacts with the page. We should capture the event, the type, and the handler ID on the server.

The snippet below shows what we do on webassembly, we should do the same in all our platforms to include logging.

aspnetcore/src/Components/Web.JS/src/Boot.WebAssembly.ts

Line 36 in c94c3b1

setDispatchEventMiddleware((browserRendererId, eventHandlerId, continuation) => {

</issue_description>

Comments on the Issue (you are @copilot in this section)

@ Thanks for contacting us.

We're moving this issue to the .NET 8 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.</comment_new>
<comment_new>@
Thanks for contacting us.

We're moving this issue to the .NET 9 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.</comment_new>
<comment_new>@
Thanks for contacting us.

We're moving this issue to the .NET 9 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
To learn more about what to expect next and how this issue will be handled you can read more about our triage process here.</comment_new>

• Fixes [Blazor] Blazor Server/Webassembly should call setEventDispatcherMiddleware to wrap event dispatching and capture logs #45674

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Pull request overview

This PR adds event dispatch logging to Blazor Server to improve visibility into user interactions. The implementation imports and registers the addDispatchEventMiddleware function to log event handler IDs at Debug level, providing debugging parity with the middleware infrastructure already used in WebAssembly (though WebAssembly uses it for heap locking rather than logging).

Key Changes

• Imports addDispatchEventMiddleware from WebRendererInteropMethods
• Registers middleware in startServerCore to log event handler IDs at Debug level
• Adds observability into user interactions alongside existing render batch logging