fix: dashboard visualization query to ensure accurate chart data (#11108)

#11065

web/src/plugins/logs/Index.vue

@@ -1940,12 +1940,22 @@ export default defineComponent({
                 searchObj?.meta?.showHistogram === true
               ) {
                 // replace hits with histogram query data
+                // Override time_offset with the full query time range so that
+                // fillMissingValues uses the correct start time. The main search
+                // time_offset only covers the current page (last N rows), which
+                // would cause the chart to display partial data.
                 searchResponseForVisualization.value = {
                   ...searchObj.data.queryResults,
                   hits: searchObj.data.queryResults.aggs,
                   histogram_interval:
                     searchObj?.data?.queryResults
                       ?.visualization_histogram_interval,
+                  time_offset: {
+                    start_time:
+                      searchObj?.data?.customDownloadQueryObj?.query?.start_time,
+                    end_time:
+                      searchObj?.data?.customDownloadQueryObj?.query?.end_time,
+                  },
                 };
 
                 // assign converted_histogram_query to dashboardPanelData