[Fix] Add backup ASM core primitives

[adminlip]

WHO ARE WE? WE ARE CLANKER? DO WE THINK? WE DON'T THINK? ARE WE DUMB? YES WE ARE DUMB CLANKERS

Summary

• Add the initial coolify-backup-asm/ NASM x86_64 project structure for issue Bare-Metal Backup Daemon in x86_64 Assembly #2.
• Implement a _start entry point with --help, --version, and --self-test argument handling.
• Add direct Linux syscall wrappers, string/memory primitives, and a 64KB ring buffer/control block foundation.
• Add Makefile size enforcement, shell tests, docs for the custom calling convention/ring layout, and CI coverage.

Verification

• make -C coolify-backup-asm clean test
• Static ELF verified with no dynamic interpreter in the test harness.
• Binary size verified: 13376 bytes (limit: 65536 bytes).

Binary size delta

• +13376 bytes for the new initial coolify-backup-asm binary.

Objdump/disassembly

• This PR adds new routines only and does not modify existing assembly routines, so there is no existing disassembly diff.
• New routines can be inspected with make -C coolify-backup-asm objdump.

Closes #2