Brummel
5cd0a3400a
Records that the codegen change was a one-line extension because the 18a bump path had centralised the allocator-symbol decision on fn_name(). Documents the runtime ABI (8-byte refcount header, ailang_rc_alloc/inc/dec) and the deliberate no-inc/dec posture: programs leak intentionally under --alloc=rc; 18c lights up the actual reference counting. Next-step plan for 18c is split into three sub-iters (clone schema / linearity check / inference + codegen) since each wants its own verification cycle.