[Wasm RyuJit] fix local type encoding

[AndyAyersMS]

Order needs to match the enum order in WasmValueType.

[AndyAyersMS]

@dotnet/jit-contrib PTAL

[Copilot]

Pull request overview

This PR fixes WASM local type encoding in the CoreCLR JIT emitter by aligning the WasmValueType → WASM binary type-code lookup table order with the WasmValueType enum order.

Changes:

• Reordered typecode_mapping in GetWasmValueTypeCode to match WasmValueType enum values.
• Updated inline comments to reflect the corrected enum-to-index mapping.

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[adamperlin]

This looks good to me, thank you for fixing this!

[AndyAyersMS]

Failure is unrelated, looks like a GC issue on arm32

  Starting:    System.Linq.Tests (parallel test collections = on [2 threads], stop on fail = off)
    System.Linq.Tests.SelectTests.Overflow [SKIP]
      Condition(s) not met: "IsStressModeEnabled"
ASSERT FAILED
	Expression: !CREATE_CHECK_STRING(pMT && pMT->Validate())
	Location:   /__w/1/s/src/coreclr/vm/object.cpp:548
	Function:   ValidateInner
	Process:    34

Opened #124153

[AndyAyersMS]

/ba-g unrelated gc issue