style(HistoryListPanel): move Clear button to top toolbar, match Export style

Moves the Clear affordance out of the "History (N)" section header and
up to the panel toolbar alongside Export, where it now uses the same
`Button variant="default"` styling. Order in the toolbar is now:
ListToggle · Clear · Export. Clear is disabled when there are no
unpinned entries to remove (pinned entries are intentionally preserved).

ToolbarButton helper is unused after this change and dropped.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: cliffhall

clients/web/src/components/groups/HistoryListPanel/HistoryListPanel.tsx

@@ -24,11 +24,6 @@ export interface HistoryListPanelProps {
   onTogglePin: (id: string) => void;
 }
 
-const ToolbarButton = Button.withProps({
-  variant: "subtle",
-  size: "sm",
-});
-
 const PanelContainer = Paper.withProps({
   withBorder: true,
   p: "lg",
@@ -107,6 +102,13 @@ export function HistoryListPanel({
               onToggle={() => setCompact((c) => !c)}
             />
           )}
+          <Button
+            variant="default"
+            onClick={onClearAll}
+            disabled={unpinnedEntries.length === 0}
+          >
+            Clear
+          </Button>
           <Button variant="default" onClick={onExport} disabled={!hasResults}>
             Export
           </Button>
@@ -138,12 +140,9 @@ export function HistoryListPanel({
 
             {unpinnedEntries.length > 0 && (
               <>
-                <Group justify="space-between">
-                  <Title order={5}>
-                    {formatHistoryTitle(unpinnedEntries.length)}
-                  </Title>
-                  <ToolbarButton onClick={onClearAll}>Clear</ToolbarButton>
-                </Group>
+                <Title order={5}>
+                  {formatHistoryTitle(unpinnedEntries.length)}
+                </Title>
                 {unpinnedEntries.map((entry) => (
                   <HistoryEntry
                     key={entry.id}