fix: combo chart time chip placement and bar chart comparison passthrough

- Combo charts now place x-axis fields in rows initially, matching the
  standard chart behavior: time chips stay in rows when no dimensions
  are present, and move to columns when dimension chips exist in rows.
- Bar chart types (bar_chart, stacked_bar, stacked_bar_normalized) no
  longer force showTimeComparison to false, allowing the global
  comparison time range to pass through to the explore URL.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: TheRillJon

web-common/src/features/canvas/components/charts/BaseChart.ts

@@ -129,10 +129,17 @@ export abstract class BaseChart<
     const timeGrain = get(this.timeAndFilterStore)?.timeGrain;
     const tddLink = getLinkStateForTimeDimensionDetail(spec, this.type);
 
+    const comparisonChartTypes = [
+      "bar_chart",
+      "stacked_bar",
+      "stacked_bar_normalized",
+    ];
+    const passComparison = comparisonChartTypes.includes(this.type);
+
     return {
       whereFilter: dimensionFilters,
       dimensionThresholdFilters,
-      showTimeComparison: false,
+      ...(passComparison ? {} : { showTimeComparison: false }),
       activePage: tddLink.canLink
         ? DashboardState_ActivePage.TIME_DIMENSIONAL_DETAIL
         : DashboardState_ActivePage.PIVOT,

web-common/src/features/canvas/components/charts/variants/ComboChart.ts

@@ -285,13 +285,13 @@ export class ComboChartComponent extends BaseChart<ComboCanvasChartSpec> {
 
     if (spec.x?.field) {
       if (spec.x.type === "temporal") {
-        columns.push({
+        rows.push({
           id: timeGrain || V1TimeGrain.TIME_GRAIN_DAY,
           title: spec.x.field,
           type: PivotChipType.Time,
         });
       } else {
-        columns.push({
+        rows.push({
           id: spec.x.field,
           title: spec.x.field,
           type: PivotChipType.Dimension,
@@ -315,6 +315,17 @@ export class ComboChartComponent extends BaseChart<ComboCanvasChartSpec> {
       });
     }
 
+    const hasDimensionRows = rows.some(
+      (r) => r.type === PivotChipType.Dimension,
+    );
+    if (hasDimensionRows) {
+      const timeChips = rows.filter((r) => r.type === PivotChipType.Time);
+      const nonTimeRows = rows.filter((r) => r.type !== PivotChipType.Time);
+      columns.push(...timeChips);
+      rows.length = 0;
+      rows.push(...nonTimeRows);
+    }
+
     const pivot: PivotState = {
       columns,
       rows,