Add the CXET HFT wolfSSL profile

[be0hhh]

Summary

• add the scoped CXET HFT build profile and marker
• split duplicate write paths into cold and hot implementations
• expose generated AES-NI and SP x86_64 assembly feature defines
• keep root-side producer and consumer ABI checks fail-closed

Verification

• CXETCPP production build with acceleration enabled
• portable CI-style CXETCPP build with acceleration disabled
• CXETCPP CTest: 77/77 passed
• hft-trader portable build and CTest: 56/56 passed
• hft-parser consumer rebuild and CTest: 19/19 passed

Scope

This PR targets the be0hhh/wolfssl fork. It is intentionally CXET-specific and is not presented as an upstream-ready wolfSSL patch series.