PackedSimd documentation does not specific underlying SIMD method.

### Type of issue

Missing information

### Description

All current intrinsic specific type methods (Avx, Sse, etc) contain the name of the underlying method that is being implemented. `PackedSimd` lacks this documentation making it difficult to understand what behavior to expect.

For example [Swizzle(Vector128, Vector128)](https://learn.microsoft.com/en-us/dotnet/api/system.runtime.intrinsics.wasm.packedsimd.swizzle?view=net-9.0#system-runtime-intrinsics-wasm-packedsimd-swizzle(system-runtime-intrinsics-vector128((system-byte))-system-runtime-intrinsics-vector128((system-byte)))) contains no information at all but the equivalent [Rust docs](https://doc.rust-lang.org/stable/core/arch/wasm32/fn.i8x16_swizzle.html) explain how out of bounds values are handled.

In addition, the reference source simply points to [PackedSimd.PlatformNotSupported.cs](https://github.com/dotnet/runtime/blob/1d1bf92fcf43aa6981804dc53c5174445069c9e4/src/libraries/System.Private.CoreLib/src/System/Runtime/Intrinsics/Wasm/PackedSimd.PlatformNotSupported.cs#L59C101-L59C143) which is not very useful.

### Page URL

https://learn.microsoft.com/en-us/dotnet/api/system.runtime.intrinsics.wasm.packedsimd?view=net-9.0

### Content source URL

https://github.com/dotnet/dotnet-api-docs/blob/main/xml/System.Runtime.Intrinsics.Wasm/PackedSimd.xml

### Document Version Independent Id

01beb992-f50a-4066-066b-50b76bb5c4e0

### Platform Id

186f97c9-af0e-c4d0-2b36-538c317ec28c

### Article author

@dotnet-bot