Pin Layout V5 default MLX pair for device evidence

[RNT56]

Summary

• Pins Pines to the Layout V5 default MLX pair:
  • mlx-swift 260c8fb16df772b8c20295529fde958fffb66369
  • mlx-swift-lm 13d3b35a9f6207fbf342c40ff7ff77cd6f0b9b5e
• Updates the runtime compatibility pair ID, Xcode package lock, generated project, and TurboQuant docs/metadata.
• Records that Layout V5 is the default device-test layout while Layout V4 remains available for legacy/comparison runs.

Validation

• bash scripts/ci/check-mlx-package-pins.sh
• swift build --disable-automatic-resolution
• swift test --disable-automatic-resolution (189 Swift Testing tests)
• swift run --disable-automatic-resolution PinesCoreTestRunner
• bash scripts/ci/run-xcode-validation.sh all
  • iOS app build without signing passed
  • iOS test build passed
  • Pines unit smoke tests passed: 29 tests, 3 device-only skips
  • Pines UI smoke tests passed: 7 tests
• git diff --check

Hardware Gate

devicectl sees GBU-12, iPhone 15 Pro Max (iPhone16,2), but it is unavailable; no online iPhone-class hardware was available in this workspace. This PR intentionally does not activate Verified, Certified, Fast mode, snapshot restore, or adaptive precision claims.

[RNT56]

Real-device TurboQuant smoke run completed on the physical iPhone target.

Device:

• Name: GBU-12
• Model: iPhone 15 Pro Max (iPhone16,2)
• Device ID: 00008130-00041C6E2EB8001C
• iOS: 26.5 (23F77)
• Architecture: arm64

Command:

xcodebuild -project Pines.xcodeproj \
  -scheme Pines \
  -destination 'platform=iOS,id=00008130-00041C6E2EB8001C' \
  -derivedDataPath build/DerivedDataDevice \
  -skipMacroValidation \
  -skipPackagePluginValidation \
  -onlyUsePackageVersionsFromResolvedFile \
  -disableAutomaticPackageResolution \
  -scmProvider system \
  -allowProvisioningUpdates \
  ONLY_ACTIVE_ARCH=YES \
  '-only-testing:PinesTests/MLXTurboQuantRuntimeSmokeTests' \
  '-skip-testing:PinesUITests' \
  test

Result:

• MLXTurboQuantRuntimeSmokeTests: 10 tests passed, 0 failed
• Physical-device Metal codec path covered by testHighBitSeedMetalCodecRoundTripWhenAvailable
• Fixed high-bit seed device path covered by testTurboQuantCacheUsesFixedHighBitSeedOnDevice
• Result bundle: build/DerivedDataDevice/Logs/Test/Test-Pines-2026.05.25_22-24-29-+0200.xcresult

Follow-up committed in 32e9ca9: hosted PinesTests on the app target because physical iOS devices cannot run tool-hosted XCTest bundles.

Scope note: this is a targeted real-device smoke pass, not a full BenchmarkReport.v1 acceptance tuple. It should not promote any model to Verified/Certified by itself.