feat(ST-354): add bulk-claim button to Sprint Backlog panel header

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

components/sprint/sprint-backlog.tsx

@@ -15,7 +15,7 @@ import { PanelNavBar } from '@/components/shared/panel-nav-bar'
 import { UserAvatar } from '@/components/shared/user-avatar'
 import { DemoTooltip } from '@/components/shared/demo-tooltip'
 import { useSprintStore } from '@/stores/sprint-store'
-import { claimStoryAction, unclaimStoryAction, reassignStoryAction } from '@/actions/stories'
+import { claimStoryAction, unclaimStoryAction, reassignStoryAction, claimAllUnassignedInActiveSprintAction } from '@/actions/stories'
 import { cn } from '@/lib/utils'
 
 const STATUS_COLORS: Record<string, string> = {
@@ -222,6 +222,24 @@ export function SprintBacklogLeft({
 }: SprintBacklogLeftProps) {
   const { sprintStoryOrder } = useSprintStore()
   const { setNodeRef, isOver } = useDroppable({ id: 'sprint-zone' })
+  const [isPending, startTransition] = useTransition()
+
+  const unassignedCount = stories.filter(s => s.assignee_id === null).length
+  const currentUserUsername = members.find(m => m.userId === currentUserId)?.username ?? null
+
+  function handleClaimAll() {
+    const unassigned = stories.filter(s => s.assignee_id === null)
+    unassigned.forEach(s => onAssigneeChange(s.id, currentUserId, currentUserUsername))
+    startTransition(async () => {
+      const result = await claimAllUnassignedInActiveSprintAction(productId)
+      if (!result.success) {
+        unassigned.forEach(s => onAssigneeChange(s.id, null, null))
+        toast.error(result.error ?? 'Claimen mislukt')
+      } else {
+        toast.success(`${result.count} ${result.count === 1 ? 'story' : 'stories'} geclaimd`)
+      }
+    })
+  }
 
   const storyMap = Object.fromEntries(stories.map(s => [s.id, s]))
   const order = sprintStoryOrder[sprintId] ?? stories.map(s => s.id)
@@ -229,7 +247,20 @@ export function SprintBacklogLeft({
 
   return (
     <div className="flex flex-col h-full">
-      <PanelNavBar title="Sprint Backlog" />
+      <PanelNavBar
+        title="Sprint Backlog"
+        actions={
+          <DemoTooltip show={isDemo}>
+            <button
+              onClick={handleClaimAll}
+              disabled={isDemo || unassignedCount === 0 || isPending}
+              className="text-xs text-primary hover:text-primary/80 disabled:opacity-40 disabled:cursor-not-allowed whitespace-nowrap"
+            >
+              {isPending ? 'Claimen…' : `Claim ongeclaimd (${unassignedCount})`}
+            </button>
+          </DemoTooltip>
+        }
+      />
       <div
         ref={setNodeRef}
         className={cn(