feat(reports): clamp report descriptions with a show more toggle

Report descriptions run to a paragraph. ReportDescription wraps Mantine's
Spoiler to clamp them to two lines, and the toggle only renders when the
text actually overflows.

PageHeader kept its subtitle on a hard truncate class, which would have
pinned the spoiler to one line, so a ReactNode subtitle now renders as-is
and owns its own layout. A string subtitle still truncates as before.

apps/edr-freight-web/backoffice/src/components/page/PageHeader.tsx

@@ -58,9 +58,15 @@ export function PageHeader({
               {meta}
             </Group>
             {subtitle ? (
-              <Text c="dimmed" size="sm" mt={4} className="truncate">
-                {subtitle}
-              </Text>
+              typeof subtitle === "string" ? (
+                <Text c="dimmed" size="sm" mt={4} className="truncate">
+                  {subtitle}
+                </Text>
+              ) : (
+                // A component subtitle handles its own layout — truncating it
+                // to one line would defeat e.g. an expandable description.
+                <div style={{ marginTop: 4 }}>{subtitle}</div>
+              )
             ) : null}
           </div>
         </Group>

apps/edr-freight-web/backoffice/src/components/reports/ReportDescription.tsx

@@ -0,0 +1,27 @@
+import { Spoiler, Text } from "@mantine/core";
+
+interface ReportDescriptionProps {
+  text: string;
+}
+
+/**
+ * Report descriptions run to a paragraph. Clamps to roughly two lines and adds
+ * a Show more toggle — Spoiler measures the content, so the toggle only appears
+ * when the text actually overflows.
+ */
+export function ReportDescription({ text }: ReportDescriptionProps) {
+  return (
+    <Spoiler
+      maxHeight={44}
+      showLabel="Show more"
+      hideLabel="Show less"
+      styles={{ control: { fontSize: "var(--mantine-font-size-xs)" } }}
+    >
+      <Text c="dimmed" size="sm">
+        {text}
+      </Text>
+    </Spoiler>
+  );
+}
+
+export default ReportDescription;

apps/edr-freight-web/backoffice/src/components/reports/ReportSection.tsx

@@ -1,8 +1,9 @@
-import { Stack, Text, Title } from "@mantine/core";
+import { Stack, Title } from "@mantine/core";
 import { useQuery } from "@tanstack/react-query";
 
 import { api } from "@/services/api";
 
+import { ReportDescription } from "./ReportDescription";
 import { ReportView } from "./ReportView";
 
 interface ReportSectionProps {
@@ -29,9 +30,7 @@ export function ReportSection({ reportKey, idKeyValue, defaultView }: ReportSect
     <Stack gap="xs">
       <div>
         <Title order={4}>{def.title}</Title>
-        <Text size="sm" c="dimmed">
-          {def.description}
-        </Text>
+        <ReportDescription text={def.description} />
       </div>
       <ReportView reportKey={reportKey} idKeyValue={idKeyValue} defaultView={defaultView} />
     </Stack>

apps/edr-freight-web/backoffice/src/components/reports/ReportView.tsx

@@ -13,6 +13,7 @@ import type { ReportFilterDef, ReportRunParams } from "@/types/reports";
 import { DataTable, DataTableFooter, usePagination, type ColumnDef } from "@edr/ui-common";
 
 import { ReportChart } from "./ReportChart";
+import { ReportDescription } from "./ReportDescription";
 import { ReportExportButton } from "./ReportExportButton";
 import { formatKpiValue, formatReportCell } from "./report-format";
 
@@ -229,7 +230,7 @@ export function ReportView({ reportKey, idKeyValue, pageHeader, defaultView }: R
       {pageHeader ? (
         <PageHeader
           title={def.title}
-          subtitle={def.description}
+          subtitle={<ReportDescription text={def.description} />}
           action={
             <Group gap="xs">
               {exportButton}