chore(checkpoint): save current v0 build state

slhx-derive/tests/surface.rs

@@ -0,0 +1,11 @@
+use slhx_derive::surface;
+
+#[surface]
+mod ui {
+    pub const EXISTING: u8 = 1;
+}
+
+#[test]
+fn surface_macro_preserves_inline_module_without_generated_file() {
+    assert_eq!(ui::EXISTING, 1);
+}