remove indirection in vertex builder

src/rendering/twn_sprites.c

@@ -242,7 +242,7 @@ void render_sprite_batch(const Primitive2D primitives[],
                 v3 = (Vec2){ c.x + t.x * +h.x - t.y * -h.y, c.y + t.y * +h.x + t.x * -h.y };
             }
 
-            push_quad_payload_to_vertex_buffer_builder(batch, &payload, v0, v1, v2, v3, uv0, uv1, uv2, uv3, sprite.color);
+            push_quad_payload_to_vertex_buffer_builder(batch, i, &payload, v0, v1, v2, v3, uv0, uv1, uv2, uv3, sprite.color);
         }
     }