Fixing minor issues in multifigure plots

src/plot/figure.cpp

@@ -467,7 +467,11 @@ const FigureLayout& Figure::layout() {
   // per row settles the answer exactly. Measuring with a floor from the previous frame
   // would be the only reason to iterate, and clearing it before the measurement pass is
   // what removes it.
-  f32 gutter = 0.0f;
+  //
+  // `set_min_y_gutter()` seeds the maximum rather than being imposed on a row before the
+  // measurement, so a reserved floor cannot widen what a row reports and then be widened
+  // by its own reservation on the next frame.
+  f32 gutter = min_y_gutter_;
   for (u32 row = 0; row < rows; ++row) {
     plots_[row].set_min_y_gutter(0.0f);
     const PlotLayout& row_layout = plots_[row].layout();