Add docs for short circuiting

[adityamandaleeka]

.NET 8 has a new feature for short circuiting routes. We should document it.

Some notes that may be useful...

When routing matches an endpoint it typically lets the rest of the middleware pipeline run before invoking the endpoint logic. If that's not necessary or desirable, there's a new option that will cause routing to invoke the endpoint logic immediately and then end the request. This can be used to efficiently respond to requests that don't require additional features like authentication, CORS, etc., such as requests for robots.txt or favicon.ico.

app.MapGet("/", () => "Hello World").ShortCircuit();

You can also use the MapShortCircuit method to setup endpoints that send a quick 404 or other status code for matched resources that you don't want to further process.

app.MapShortCircuit(404, "robots.txt", "favicon.ico");

More info:

• Issue: Add Route Short Circuit middleware aspnetcore#46071
• PR: Add short circuit in routing aspnetcore#46713

EDIT by @Rick-Anderson to add the following metadata

Provide link in https://learn.microsoft.com/en-us/aspnet/core/fundamentals/middleware/ doc to ShortCircuit

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Document Details

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• ID: 32374077-e02e-d6a6-1cea-05e58447b7cd
• Version Independent ID: 86aeab13-1c25-9fc1-4e56-0390cb40c242
• Content: Routing in ASP.NET Core
• Content Source: aspnetcore/fundamentals/routing.md
• Product: aspnet-core
• Technology: aspnetcore-fundamentals
• GitHub Login: @Rick-Anderson
• Microsoft Alias: riande

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Associated WorkItem - 85531

[adityamandaleeka]

cc: @Tratcher