compiler: separate package exports from entry roots

selfhost/cmd/w6l/main.ww

@@ -249,8 +249,10 @@ export fn main(argc: i32, argv: **u8) i32 = {
 
 	let l: *lnk = mklnk();
 
-	// Seed _start so libwwrt-style start.o is recognised as wanted.
+	// Seed both accepted entries before archive loading. This lets the root
+	// package arrive as an ordinary selective-pull archive.
 	intern(l, "_start");
+	intern(l, "main");
 
 	// Load positional inputs first (preserving order).
 	let k: i32 = 0;