lib/fnmatch: explicit '\\': u8 cast; fnmatch graduates to the byte-id gate

wwstage over-rejects harec's flexible-rune-const narrow (rune lit
promotes into any int whose range fits — harec check.c:1910,
types.c promote_flexible); explicit cast until that promotion lands
in ww (#29, revert to bare '\\' then). With the enum-as fix fnmatch
is byte-identical across stages: 989 #59.14 graduates
M_WWREJECT -> M_ID, transferring 972's cstage 8/8 behavior to the
provably-identical wwstage binary — the dark-regression gate. (#29)

lib/fnmatch/fnmatch.ww

@@ -123,7 +123,8 @@ fn pat_next(pat: str, pos: *i32, fl: flag) (u8 | star | question | bracket | end
 			*pos += 1;
 			return c2;
 		};
-		return '\\';
+		// #29: wwstage over-rejects the implicit flexible-rune-const narrow (harec promote_flexible accepts); explicit cast until flexible-const promotion lands — revert to bare '\\' then.
+		return '\\': u8;
 	};
 	return c;
 };

test/wcc/989_lib_byteid.c

@@ -154,8 +154,12 @@ static const struct ent ents[] = {
 	/* -------- wwstage front-end gaps (task #59) -------------- */
 	{ .fixture = "lib/crypto/sha256/sha256_test.ww",
 	  .mode = M_WWREJECT, .cite = "#59.13" },
+	/* #59.14 graduated to M_ID by #27: the #27b enum-as-int cgen fix
+	 * (value passthrough, not a tagged assertion) + the fnmatch.ww:126
+	 * `'\\': u8` explicit cast (the rune-lit→u8 narrow w6c_ww rejects at
+	 * a checked position) make w6c_ww compile fnmatch byte-identically. */
 	{ .fixture = "lib/fnmatch/fnmatchtest.ww",
-	  .mode = M_WWREJECT, .cite = "#59.14" },
+	  .mode = M_ID, .cite = "#59.14 graduated by #27" },
 	/* #59.15 shlex graduated to M_ID by B-full Layer 1 (#14 nominal
 	 * typeeqast): the cross-module bare-vs-qualified variant forward
 	 * w6c_ww over-rejected now compiles byte-identically. */