Add missing non-bubbling DOM events to EventDelegator

[Copilot]

Add missing non-bubbling DOM events to EventDelegator

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Add all remaining non-bubbling DOM events to EventDelegator.ts

Description

Blazor's event delegation requires a fixed list of non-bubbling events to register capture listeners instead of bubble listeners. The existing list covered ~95% of use cases but was missing several events per MDN documentation.

Added events (verified via MDN bubbles: false):

• beforeunload - Window beforeunload
• contextlost / contextrestored - Canvas 2D context events
• formdata - Form data construction
• invalid - Form validation
• lostpointercapture - Pointer capture release
• resize - Window resize
• securitypolicyviolation - CSP violation
• slotchange - Web Components slot change

Events verified to bubble (NOT added):

• select, scrollend, gotpointercapture, fullscreenchange, fullscreenerror

Also sorted the list alphabetically for maintainability.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Support all nonbubbling events</issue_title>
<issue_description>Today, Blazor has a fixed list of nonbubbling DOM events in EventDelegator.ts. It covers maybe 95% of what anyone will ever want to use. However there are some more obscure nonbubbling DOM events, so we should check the complete list at https://developer.mozilla.org/en-US/docs/Web/Events and consider adding all the rest.

Alternatively if one day we didn't do event delegation, we wouldn't need any special cases here in the first place.</issue_description>

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

@ We've moved this issue to the Backlog milestone. This means that it is not going to be worked on for the coming release. We will reassess the backlog following the current release and consider this item at that time. To learn more about our issue management process and to have better expectation regarding different types of issues you can read our [Triage Process](https://github.com/dotnet/aspnetcore/blob/main/docs/TriageProcess.md). @ We've moved this issue to the Backlog milestone. This means that it is not going to be worked on for the coming release. We will reassess the backlog following the current release and consider this item at that time. To learn more about our issue management process and to have better expectation regarding different types of issues you can read our [Triage Process](https://github.com/dotnet/aspnetcore/blob/main/docs/TriageProcess.md).

• Fixes Support all nonbubbling events #36928

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