Fix unused logicalHeight variable left over from CodeRabbit fix

Removing it in favor of viewportHeight for the vertical fit ratio left
the declaration itself dead code, which the CI lint step flags as an
error rather than a warning.

apps/nextjs/src/components/board/sections/grid/section-grid.tsx

@@ -149,7 +149,6 @@ export const SectionGrid = ({
   const effectiveCanvasScale = Number.isFinite(canvasScale) && canvasScale > 0 ? canvasScale : 1;
   const outerCardInset = section.kind === "container" ? (2 * 10) / effectiveCanvasScale : 0;
   const logicalWidth = getLogicalGridSize(columnCount) - outerCardInset;
-  const logicalHeight = getLogicalGridSize(rowCount) - outerCardInset;
   const viewportHeight = getLogicalGridSize(viewportRowCount) - outerCardInset;
   // Items are positioned in a coordinate space sized to the *un-inset* column/row count
   // (fullGridWidth/Height below - see getLogicalItemStyle), but logicalWidth/Height above are
@@ -162,11 +161,11 @@ export const SectionGrid = ({
   const fullGridWidth = getLogicalGridSize(columnCount);
   const fullGridHeight = getLogicalGridSize(rowCount);
   // For a scrollable container, rowCount covers *all* content rows, not just the visible card -
-  // fullGridHeight/logicalHeight grow together with it, so their ratio drifts toward 1 as content
+  // fullGridHeight grows right along with it, so a ratio built from it drifts toward 1 as content
   // grows regardless of the (fixed) inset, under-scaling relative to what the actually-visible
   // viewport needs and clipping the bottom of the visible rows. viewportHeight/viewportRowCount
-  // describe the real visible card size in both cases (they equal logicalHeight/rowCount when not
-  // scrollable), so use those instead.
+  // describe the real visible card size in both cases (they equal the non-scrollable values when
+  // rowCount and viewportRowCount are the same), so use those instead.
   const fullViewportHeight = getLogicalGridSize(viewportRowCount);
   // A uniform zoom is required (not a non-uniform transform scale(x, y)) - --board-canvas-ui-scale
   // is a single scalar that every icon/text/custom-CSS size compensation in the app multiplies