refactor: move PipelineItems from Zustand to Provider→Service→React Query

PipelineItems are domain data and must not live in Zustand. Moves the
full stack to the correct layer: MockupPipelineProvider (localStorage
persistence + seed fallback) → pipelineService → usePipeline hooks
(useQuery for reads, useMutation for writes with cache invalidation).

pipelineStore is now UI-only: dialogOpen, pendingItem, openSavedDialog,
closeSavedDialog. All consumers updated to use the new hooks.

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

src/pages/demand/Anfragen.tsx

@@ -6,7 +6,7 @@ import {
 } from '@mui/material'
 import { Search, Send, Paperclip, ArrowLeft, Bot, Building2, Kanban } from 'lucide-react'
 import { mockInquiries } from '../../mock-data/inquiries'
-import { usePipelineStore } from '../../stores/pipelineStore'
+import { usePipelineItems, useMoveStage } from '../../hooks/usePipeline'
 import { useToastStore } from '../../stores/toastStore'
 import type { InquiryMessage } from '../../domain/inquiry'
 import { STAGE_ORDER, STAGE_LABELS, detectKiStage } from './anfragenKiDetection'
@@ -34,7 +34,8 @@ const FILTER_TABS = [
 export default function Anfragen() {
   const navigate = useNavigate()
   const [searchParams] = useSearchParams()
-  const { findByPropertyId, findByInquiryId, moveStage } = usePipelineStore()
+  const { data: pipelineItems = [] } = usePipelineItems()
+  const { mutate: moveStage } = useMoveStage()
   const showToast = useToastStore(s => s.showToast)
 
   const preselectedId = searchParams.get('inquiry')
@@ -65,8 +66,8 @@ export default function Anfragen() {
 
   // Pipeline link for currently selected inquiry
   const linkedPipelineItem = selected?.propertyId
-    ? findByPropertyId(selected.propertyId)
-    : (selected ? findByInquiryId(selected.id) : undefined)
+    ? pipelineItems.find(i => i.propertyId === selected.propertyId)
+    : (selected ? pipelineItems.find(i => i.inquiryId === selected.id) : undefined)
 
   useEffect(() => {
     if (threadRef.current) {
@@ -112,13 +113,13 @@ export default function Anfragen() {
     const ki = detectKiStage(text)
     if (ki && selected) {
       const pipelineItem = selected.propertyId
-        ? findByPropertyId(selected.propertyId)
-        : findByInquiryId(selectedId)
+        ? pipelineItems.find(i => i.propertyId === selected.propertyId)
+        : pipelineItems.find(i => i.inquiryId === selectedId)
       if (pipelineItem) {
         const currentIdx = STAGE_ORDER.indexOf(pipelineItem.stage)
         const targetIdx = STAGE_ORDER.indexOf(ki.stage)
         if (targetIdx > currentIdx) {
-          moveStage(pipelineItem.id, ki.stage)
+          moveStage({ id: pipelineItem.id, stage: ki.stage })
           setKiAlert({ title: pipelineItem.title, stage: STAGE_LABELS[ki.stage] })
         }
       }
@@ -180,7 +181,7 @@ export default function Anfragen() {
               key={inq.id}
               inq={inq}
               isSelected={inq.id === selectedId}
-              hasPipeline={!!(inq.propertyId ? findByPropertyId(inq.propertyId) : findByInquiryId(inq.id))}
+              hasPipeline={!!(inq.propertyId ? pipelineItems.find(i => i.propertyId === inq.propertyId) : pipelineItems.find(i => i.inquiryId === inq.id))}
               onSelect={handleSelect}
             />
           ))}

src/pages/demand/Pipeline.tsx

@@ -8,7 +8,7 @@ import {
 } from '@dnd-kit/core'
 import type { DragEndEvent, DragStartEvent } from '@dnd-kit/core'
 import { TrendingUp } from 'lucide-react'
-import { usePipelineStore } from '../../stores/pipelineStore'
+import { usePipelineItems, useMoveStage } from '../../hooks/usePipeline'
 import { AddToPipelineDialog } from '../../components/shortlist'
 import type { PipelineItem, PipelineStage } from '../../domain/pipeline'
 import { STAGES } from '../../components/pipeline/pipelineConstants'
@@ -20,7 +20,8 @@ import { DetailPanel } from '../../components/pipeline/PipelineDetailPanel'
 
 export default function Pipeline() {
   const navigate = useNavigate()
-  const { items, moveStage } = usePipelineStore()
+  const { data: items = [] } = usePipelineItems()
+  const { mutate: moveStage } = useMoveStage()
   const [selectedItem, setSelectedItem] = useState<PipelineItem | null>(null)
   const [activeId, setActiveId] = useState<string | null>(null)
   const [overId, setOverId] = useState<string | null>(null)
@@ -53,7 +54,7 @@ export default function Pipeline() {
     const targetStage = over.id as PipelineStage
     const item = items.find(i => i.id === active.id)
     if (item && item.stage !== targetStage) {
-      moveStage(item.id, targetStage)
+      moveStage({ id: item.id, stage: targetStage })
     }
   }