fix scaling issues

src/renderer/renderer_metal.mm

@@ -801,6 +801,14 @@ void renderer_end_frame(Renderer *r, Clay_RenderCommandArray render_commands) {
     r->frame_index++;
 }
 
+void renderer_set_font_scale(Renderer *r, float scale) {
+    float target_size = 15.0f * scale;
+    if (fabsf(target_size - r->font_atlas_size) < 0.1f) return;
+    r->font_texture = nil;
+    r->font_sampler = nil;
+    create_font_atlas(r, target_size);
+}
+
 void renderer_resize(Renderer *r, int32_t width, int32_t height) {
     if (width <= 0 || height <= 0) return;
     r->width = width;