fix(webapp): carry-guard column reaches the chart points, Total naming in the UI

The sampled guard was queried but dropped when rows became chart points,
so the back-fill guard always read zero and pre-cap history was still
overwritten; the guard column is now copied onto each point. User-visible
strings move from Combined to Total, matching the perKey/total vocabulary.

Author: matt-aitken

apps/webapp/app/components/queues/QueueMetricCards.tsx

@@ -170,6 +170,7 @@ export function QueueMetricChart({
         };
         const hasSamples = sampleCountColumn ? toNumber(r[sampleCountColumn]) > 0 : true;
         for (const s of series) point[s.key] = hasSamples ? toNumber(r[s.key]) : null;
+        if (carryBackfillGuard) point[carryBackfillGuard] = toNumber(r[carryBackfillGuard]);
         return point;
       })
       .filter((p) => Number.isFinite(p.bucket));

apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.queues/route.tsx

@@ -903,7 +903,7 @@ function QueuesWithMetricsView() {
                               }
                               content={
                                 <>
-                                  Combined limit: at most{" "}
+                                  Total limit: at most{" "}
                                   {Math.min(
                                     queue.concurrency.combined.current,
                                     environment.concurrencyLimit
@@ -1997,7 +1997,7 @@ function ClassicQueuesView() {
                               }
                               content={
                                 <>
-                                  Combined limit: at most{" "}
+                                  Total limit: at most{" "}
                                   {Math.min(
                                     queue.concurrency.combined.current,
                                     environment.concurrencyLimit

apps/webapp/app/routes/_app.orgs.$organizationSlug.projects.$projectParam.env.$envParam.queues_.$queueParam/route.tsx

@@ -488,7 +488,7 @@ function OverviewCharts({
         />
         {hasTotalLimit ? (
           <QueueDetailChartCard
-            title="Combined concurrency"
+            title="Total concurrency"
             info={
               <>
                 Runs in flight across ALL concurrency keys (
@@ -506,7 +506,7 @@ function OverviewCharts({
             timeRange={timeRange}
             queueName={queueName}
             series={[
-              { key: "cap", label: "Combined limit", color: COLORS.limit },
+              { key: "cap", label: "Total limit", color: COLORS.limit },
               { key: "running", label: "Running", color: COLORS.running },
             ]}
             thresholdStroke={{