ludic.base: bake_maps refuses a first input without {map} (it would test one path for every map: all or none); bake_expand says a {map} row is expanded only with a key from bake_maps

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/ludic.base/tests/baked_expand_test.ludic

@@ -28,6 +28,8 @@ program BakedExpandTest {
     expect_eq(len(maps), 2)
     expect_eq(maps[0], "a")
     expect_eq(maps[1], "b")
+    # a first input without {map} tests one path for every map: refused, not all or none
+    expect_eq(len(bake_maps_in(root() + "/maps", root() + "/maps/a/ground_layers.lres")), 0)
   }
 
   test "a map's inputs: {map} put, the glob's matches sorted byte by byte, dot-names out" {