Document breaking change: Arm64 SVE NonFaulting loads require mask parameter

[Copilot]

This PR adds comprehensive breaking change documentation for .NET 10, where all Arm64 SVE NonFaulting load APIs now require a mask parameter as the first argument.

Changes Made

New Documentation:

• Created docs/core/compatibility/core-libraries/10.0/sve-nonfaulting-loads-mask-parameter.md with complete breaking change documentation following the standard template

Navigation Updates:

• Added entry to docs/core/compatibility/toc.yml under Core .NET libraries section for .NET 10
• Added table entry to docs/core/compatibility/10.0.md with proper classification as binary/source incompatible

Breaking Change Details

This change affects all 25 NonFaulting load APIs in the System.Runtime.Intrinsics.Arm.Sve namespace. Previously, these methods took only an address parameter:

// .NET 9 behavior
Vector<short> result = Sve.LoadVectorByteNonFaultingZeroExtendToInt16(address);

Now they require a mask parameter as the first argument:

// .NET 10 behavior
Vector<short> result = Sve.LoadVectorByteNonFaultingZeroExtendToInt16(
    Sve.CreateTrueMaskInt16(), address);

The change was necessary because non-faulting loads update the FFR (First Fault Register) based on which vector lanes are loaded, making the standard ConditionalSelect approach invalid for masked operations.

Documentation Standards

• Follows Microsoft Writing Style Guide
• Uses proper xref syntax for API cross-references
• Passes all markdownlint validation
• Includes clear migration guidance and code examples
• Documents technical reasoning behind the change

Fixes #47439.

---

💬 Share your feedback on Copilot coding agent for the chance to win a $200 gift card! Click here to start the survey.

---

Internal previews

📄 File	🔗 Preview link
docs/core/compatibility/10.0.md	Breaking changes in .NET 10
docs/core/compatibility/core-libraries/10.0/sve-nonfaulting-loads-mask-parameter.md	Arm64 SVE nonfaulting loads require mask parameter
docs/core/compatibility/toc.yml	docs/core/compatibility/toc

[gewarren]

cc @a74nh.

[a74nh]

Technical contents of this LGTM. I'm not sure what the expected style or depth of this should be so I can't comment on that part.

[BillWagner]

This LGTM @gewarren Let's