fix: macOS ARM64 build compatibility

[minnow54426]

Summary

• Guard -maes CMake flag behind non-ARM check (AES-NI always available on ARM64)
• Make -lrt linker dependency Linux-only (not available on macOS)
• Fix size_t vs uint64_t mismatch in check_sig.h
• Remove bridge_func declaration from fhe_types_v2.h (moved to Go c-shared build to avoid duplicate symbols)
• Update lattigo submodule to fix: macOS ARM64 and C++ compatibility for CGO headers lattigo#9 (macOS ARM64 CGO header fixes)

Dependencies

• Requires: fix: macOS ARM64 and C++ compatibility for CGO headers lattigo#9

Test plan

• Build lattisense on macOS ARM64 with updated lattigo submodule
• Build lattisense on Linux x86_64 — no regressions
• Run latti-ai encrypted inference end-to-end

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