port os functions, add testing module

src/ui/ui.c

@@ -1,3 +1,5 @@
+#include "ui.gen.c"
+
 fn ui_caret_t ui_caret_clamp(ui_caret_t c, i32 min, i32 max) {
     return (ui_caret_t){CLAMP(c.e[0],min,max), CLAMP(c.e[1],min,max), c.ifront};
 }