fix: disable mimalloc architecture optimizations on Linux ARM64

[Brooooooklyn]

@node-rs/bcrypt@1.10.8 crashes during module loading on Raspberry Pi 4 because its bundled mimalloc allocator emits unconditional ARMv8.1 LSE atomics. Enable mimalloc-safe/no_opt_arch for Linux AArch64, covering GNU and musl, while preserving the existing macOS and Windows AArch64 optimization settings.

The feature sets both MI_OPT_ARCH=OFF and MI_NO_OPT_ARCH=ON; the latter prevents mimalloc's ARM64 defaults from enabling architecture optimizations again. Existing allocator TLS and exit-collection features are preserved.

Fixes #1199.

Validation:

• Checked Cargo feature resolution for Linux AArch64 GNU/musl, macOS AArch64, Windows AArch64, Linux x86_64, Android AArch64, FreeBSD AArch64, and WASI. Only Linux AArch64 enables no_opt_arch.
• Rebuilt the GNU ARM64 bcrypt addon with Rust 1.98.0 and Clang 14, and confirmed both CMake overrides and the absence of the forced -march=armv8.1-a compiler flag.
• The rebuilt addon passes loading, synchronous/asynchronous hashing and verification, salt generation, and worker loading/execution/exit under QEMU Cortex-A72, Cortex-A53, and max.

Runtime validation used emulation; physical Raspberry Pi testing and native macOS/Windows builds were not run.

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-09-10T02:51:26.386785Z	61f7134	PR opened

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