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

Every section banner dies (103 -> 0) across test/lang, the observer
suites, the C carriers, and the five comment-heavy corpus fixtures;
banner provenance (#N cites, carrier numbers, repair-cluster labels)
folded into headers or adjacent WHY comments. Narration deleted; row
provenance, ref cites, divergence pins, and layout contracts kept
(fwd-ref decl-order guards and bootstrap-gate corpus rationale
restored where the sweep over-cut). Comment-only proven: all 3742
wwbuild workdir .s byte-identical before/after; test-commit and
test-byteid (161 lang + 1399 data, 0 pinned-divergent) green.

test/wcc/989_dynentry_run.c

@@ -44,8 +44,6 @@ runwait(const char *cmd)
 	return 1;
 }
 
-/* Harvest up to `max` default-versioned libc text exports into syms[][].
- * Returns the count, or -1 if nm/libc unavailable. */
 static int
 harvest_syms(const char *libc, char syms[][32], int max)
 {
@@ -68,8 +66,6 @@ harvest_syms(const char *libc, char syms[][32], int max)
 	return n;
 }
 
-/* Build with `driver` into <tmpdir>/main, run, return exit code (or -1 on
- * build failure). Sets *outbin to the produced binary path. */
 static int
 build_run(const char *driver, const char *src, const char *libdir,
     const char *tmpdir, char *outbin, size_t obsz)
@@ -119,7 +115,8 @@ main(void)
 	}
 	int fail = 0, total = 0;
 
-	/* ---- big: ~160 gated dead PLT calls, return 42 ---- */
+	/* big: the s%03d calls are gated dead — they exist only to force
+	 * enough PLT/dynsym entries to push the headers past one page. */
 	char bigsrc[1024], smallsrc[1024];
 	snprintf(bigsrc, sizeof bigsrc, "%s/big.ww", td);
 	snprintf(smallsrc, sizeof smallsrc, "%s/small.ww", td);
@@ -140,7 +137,6 @@ main(void)
 		goto out;
 	}
 
-	/* ---- small: 1 dyn sym, headers fit the page ---- */
 	f = fopen(smallsrc, "wb");
 	if (!f) {
 		perror(smallsrc);