Cap Metro maxWorkers to leave host cores free for the device under test#152
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…able GitHub-hosted runners only have 2-4 cores, so an emulator claiming a device-profile default of 4 vCPUs oversubscribes the host alongside Metro and the Node test session during startup. Bake a fixed hw.cpu.ncore=2 into each AVD's config.ini (fixed, not host-derived, so snapshots stay portable across runner sizes), regenerate incompatible cached AVDs, roll the AVD cache key so old caches are replaced once, and add a non-fatal warning when KVM/HVF acceleration looks unavailable.
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…ed action Now that the action has a real dependency on platform-android for EMULATOR_CPU_CORES, drop the local copy of getHostAndroidSystemImageArch and import the original, which is behaviorally identical. The local resolveAvdCachingEnabled stays: it is intentionally simpler than the platform-android variant, which also gates on interactivity.
Share a 2-4 core guest allocation between Android AVD creation, compatibility checks, action cache keys, and Metro consumers. This preserves CI behavior while allowing larger development hosts to use four emulator vCPUs.
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Describe the user-visible benefit of adaptive emulator CPU allocation.
GitHub-hosted CI runners are small (2-4 cores), and Metro's default maxWorkers formula can claim every host core for transform workers. The Android emulator is now pinned to 2 vCPUs and the iOS simulator runs as host processes, so leaving no headroom starves the device right when both are busiest, at startup. Reserve 2 host cores for the device and only ever lower Metro's resolved maxWorkers to respect that, never raise it. Also fixes a pre-existing @nx/dependency-checks lint failure in this package (missing "vite" from ignoredDependencies, unlike every sibling package's eslint config) that was blocking commits here.
Use the shared host-derived guest allocation so Metro reserves exactly the cores granted to the emulator. This retains 2-core CI behavior and restores a 4-core emulator budget on 8-core hosts.
Describe the user-visible startup responsiveness benefit.
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User impact
Harness test runs stay more responsive by balancing Metro work with the device under test, reducing slowdowns on larger development machines. Small CI runners behave as before.
Depends on #151; retarget to
mainafter it merges.