[shantanu2002git]

Fix OpenAPI floating-point union schema in .NET 10

• You've read the Contributor Guide and Code of Conduct.
• You've included unit or integration tests for your change, where applicable.
• You've included inline docs for your change, where applicable.
• There's an open issue for the PR that you are making.

Summary of the changes (Less than 80 chars)

Fix incorrect object constraint for OpenAPI floating-point unions

Description

Fixes #69604.

When JsonNumberHandling.AllowNamedFloatingPointLiterals is enabled, the
.NET 10 OpenAPI schema generation can produce an incorrect object type
constraint for a floating-point property using anyOf.

This makes the generated schema unsatisfiable because numeric values cannot
satisfy the outer object constraint.

This change removes the incorrect JsonSchemaType.Object assignments when
reading anyOf and oneOf schemas.

A regression test has also been added to verify that named floating-point
literals generate the expected schema without the incorrect outer object
constraint.

This is a servicing fix for the .NET 10 release branch corresponding to the
behavior already corrected on main.

Fixes #69604.

[dotnet-policy-service]

Thanks for your PR, @shantanu2002git. Someone from the team will get assigned to your PR shortly and we'll get it reviewed.

[utsavjain2809]

Hey @shantanu2002git, CI flagged a couple of issues in the test: CreateBuilder doesn’t accept the numberHandling parameter on release/10.0, and there’s an extra blank line flagged by the style check. Sharing in case you haven’t had a chance to check the results yet.

[Youssef1313]

Please assert the full JSON document, similar to what this test does:

aspnetcore/src/OpenApi/test/Microsoft.AspNetCore.OpenApi.Tests/Services/OpenApiSchemaService/OpenApiSchemaService.PolymorphicSchemas.cs

Lines 340 to 341 in 1c93845

	var actual = await document.SerializeAsJsonAsync(OpenApiSpecVersion.OpenApi3_2);
	var expected = """

[shantanu2002git]

Thanks for the feedback. I’ve updated the regression test to assert the full serialized OpenAPI JSON document, following the pattern from the referenced test.

[dotnet-policy-service]

Looks like this PR hasn't been active for some time and the codebase could have been changed in the meantime.
To make sure no conflicting changes have occurred, please rerun validation before merging. You can do this by leaving an /azp run comment here (requires commit rights), or by simply closing and reopening.