toolchain: banner purge + WHY-only comment sweep (rule 8)

selfhost/, cmd/, internal/ join the tree-wide sweep: every section
banner dies (91 selfhost + the cmd C-style dividers -> 0); narration
and stale contracts deleted (pre-#22 bundler notes, retired
single-PT_LOAD and no-archive claims, superseded ABI tables); every
ref/harec/qbe cite, task cite, encoding/ELF contract, and rule-10
twin pointer kept; lost lifetime/rationale lines restored where the
sweep over-cut (elf_globals ownership, kwtab linear-scan). Comment-
only proven: all five wwstage tool binaries byte-identical across
the sweep; test-commit, test-byteid (161+1399, 0 pinned-divergent),
and test-bootstrap (fixed point + 991-995 byte-id) all exit 0.
The read-through banked 66 latent-bug leads (checkpoint).

internal/wwpackage/package.ww

@@ -400,7 +400,6 @@ fn pkgdedup(ss: []str) []str = {
 	return out;
 };
 
-// Decimal value, or -1 on empty, non-digit, or overflow past max.
 fn pkgparsedec(s: str, max: i64) i64 = {
 	if (s.len == 0) { return -1i64; };
 	let i: i32 = 0;