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 Withdrawn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.

lib/ww/parse/parse.ww

@@ -411,6 +411,22 @@ export fn parsefile(p: *parser) *node = {
 			p.curmod = name;
 			continue;
 		};
+		// `//ww:module-reset` — bundle boundary before a package-less
+		// file. Reset curmod to "" so the file's decls (and its own
+		// `import os;`) are attributed to the primary module, not the
+		// preceding bundled package. Codegen-neutral: "" curmod keeps
+		// bare symbols. (#16 option-B; closes task #11.)
+		// Driver-emitted ONLY before package-less files; a hand-placed
+		// directive after a mid-file `package` would strip subsequent
+		// decls to bare — that usage is deliberate-only.
+		if (p.curkind == tkind.TK_MODRESET) {
+			advance(p);
+			let empty: str;
+			empty.ptr = nil;
+			empty.len = 0;
+			p.curmod = empty;
+			continue;
+		};
 		let attrs = parseattrs(p);
 		let exported: i32 = 0;
 		if (p.curkind == tkind.TK_EXPORT) { exported = 1; advance(p); };