hal/smp.c: dense logical core ids, a heap-sized core table, one-at-a-time
bring-up under a 1 s bound, park-wake reporting at the idle point.
amd64: MADT enumeration, a relocation-free real->long-mode trampoline
copied below 1 MiB, INIT-SIPI-SIPI via the LAPIC ICR; QEMU -smp 2.
Core 1 reports online with GS on its own block, parks with 0 wakes;
aarch64/riscv64 report 1 core until MC-1b/c. 3-ISA acceptance clean.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
