wcc+ww: //ww:module-reset boundary directive; package-less files keep module "" (#16 PREP-main)

Driver twins emit the line-comment directive only before package-less
files (peekpackage==nil); both lexers tokenize it (TK_MODRESET, appended
=87 so existing token values hold) and both parsers reset curmod — a
package-less file's decls get module "" instead of inheriting the last
bundled package (the sticky-curmod leak, task #11). Withdrawn
alternative: injecting 'package main' flips non-entry symbols
bare->main-prefixed (FFI-visible, broke 764). Codegen-neutral by proof:
bare symbols preserved, both stages emit byte-identical asm for a
directive-bearing combined. Transitional until strict-package rejects
package-less files outright. Includes 737 bad-deep pin for the
PREP-peek >2048 edge + 904/toktest rows for the new token.

cmd/wcc/ww.h

@@ -180,6 +180,10 @@ typedef enum {
 	TK_YIELD,	/* `yield expr;` — value-return from a match arm */
 	TK_ENUM,	/* Hare-style `enum [storage] { ... }` type form */
 	TK_MODULE,	/* `module foo;` — directory-as-module declaration */
+	TK_MODRESET,	/* `//ww:module-reset` — driver bundle boundary: reset
+			 * curmod to NULL before a package-less file's bytes
+			 * (#16 option-B; the package-less-entry attribution fix
+			 * that replaces the withdrawn `package main` inject). */
 
 	TK_LAST		/* sentinel for tables */
 } Tkind;
@@ -207,6 +211,9 @@ struct Lex {
 	i32	col;
 	Arena	*a;		/* token-text arena */
 	int	errs;
+	int	modreset;	/* a `//ww:module-reset` directive was seen in
+				 * the last skipped run; lexnext emits TK_MODRESET
+				 * before the next real token. */
 };
 
 void	lexinit(Lex*, Arena*, const char *file, const char *src, u64 len);