Don't find witnesses for typars with conditional constraints, part 2

[Smaug123]

Description

This expands the fix from #19123 to cover the entire TType DU.
Fixes #19118 even more; many (though not all) of the added test cases failed before this change.

I have not extended the tests in tests/FSharp.Core.UnitTests/FSharp.Core/Microsoft.FSharp.Quotations/FSharpQuotations.fs which I added in the previous PR.

I think this also doesn't require release notes; I don't have permission to add the NO_RELEASE_NOTES label.

The change is Claude Opus 4.5.

Checklist

• Test cases added

• Performance benchmarks added in case of performance changes

• Release notes entry updated:

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  • More inlines for Result module. (PR #16106)
  • Correctly handle assembly imports with public key token of 0 length. (Issue #16359, PR #16363)
    *while! (Language suggestion #1038, PR #14238)

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[github-actions]

❗ Release notes required

@Smaug123,

Caution

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Change path	Release notes path	Description
src/Compiler	docs/release-notes/.FSharp.Compiler.Service/10.0.200.md	No release notes found or release notes format is not correct

[Smaug123]

Refactored the existing tests so that the tests are parameterised, by the way; and added loads more tests.