lib/ww/lex + w6a/parse: amalloc β grow → alloc([], n)! (β-1)
Phase 0 first β-batch. 4 amalloc sites across 2 β grow loops:
- lib/ww/lex/lex.ww:570,592 lexstr string-literal escape buf
- selfhost/cmd/w6a/parse.ww:513,548 DATA "..." escape-payload buf
Both follow the established α-per-alloc shape with loop logic left
manual: `*u8 = amalloc(_, cap): *u8` → `[]u8 = alloc([], cap)!`,
inner copy `nb[i] = old[i]` unchanged (slice indexing emits identical
asm to *u8 indexing — no .len bounds compare), `.ptr` extracted at
the *u8 consumer (s.ptr, pr.bytes). Bear-trap N/A — byte count tracked
in locals (nb, blen), slice .len = 0 never read.
Verified 132/132 + 995_self_rebuild byte-identity.
Hojun-Cho
d9f097250b