feat: F030 Anfragencenter — Aktive & Latente Anfragen + Angebot-Wizard

Neuer Menüpunkt «Anfragencenter» (ehemals «Eingehende Bedarfe»):

Aktive Anfragen:
- Split-View: Anfrageliste (Liste/Grid-Toggle) + Chat-Detailansicht
- Chat-Verlauf mit Sender-Styling (Mieter links, Supply rechts)
- Antwortformular mit Betreff, Nachricht, Anhänge, Statuswechsel
- Zugehörige Property Card neben dem Chat

Latente Anfragen:
- Drei-Spalten-Layout: Need-Liste | Need-Detail | Eigene Objekte
- Need Cards mit AI-Zusammenfassung, Must-Haves, Präferenzen
- Eigene Portfolio-Objekte sortiert nach deterministischem Match-Score
- Checkbox-Selektion für Angebotsauswahl

Angebot-Wizard (4 Schritte):
- Schritt 1: Objekte auswählen (mit Score-Vorschau)
- Schritt 2: PDF-Vorschau + editierbare Textfelder
- Schritt 3: Angebot prüfen & bestätigen
- Schritt 4: Nachricht an Suchenden mit KI-generierter Mail

Architektur:
- Domain: Inquiry, LatentNeed, OfferDraft Types
- Provider: IInquiryProvider, ILatentNeedProvider, IOfferProvider + Mockups
- Services: inquiryService, latentNeedService, offerService
- Hooks: useInquiries, useLatentNeeds, useOffers (TanStack Query)
- Store: offerWizardStore (Zustand, lokaler Wizard-State)
- 27 neue Komponenten, alle Loading/Empty/Error States

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

src/stores/offerWizardStore.ts

@@ -0,0 +1,91 @@
+import { create } from 'zustand'
+import type { Attachment } from '../domain/inquiry'
+
+export type OfferStep = 'select_properties' | 'pdf_review' | 'checked' | 'send'
+
+interface OfferWizardState {
+  isOpen: boolean
+  selectedNeedId: string | null
+  needTitle: string
+  selectedPropertyIds: string[]
+  currentStep: OfferStep
+  offerDraftId: string | null
+  editableFields: Record<string, string>
+  pdfPreviewReady: boolean
+  messageDraft: string
+  messageSubject: string
+  attachments: Attachment[]
+  open(needId: string, needTitle: string): void
+  close(): void
+  toggleProperty(id: string): void
+  setSelectedProperties(ids: string[]): void
+  setStep(step: OfferStep): void
+  setOfferDraftId(id: string): void
+  updateField(fieldId: string, value: string): void
+  setPdfReady(): void
+  setMessageDraft(text: string): void
+  setMessageSubject(s: string): void
+  addAttachment(a: Attachment): void
+  removeAttachment(id: string): void
+  reset(): void
+}
+
+export const useOfferWizardStore = create<OfferWizardState>((set) => ({
+  isOpen: false,
+  selectedNeedId: null,
+  needTitle: '',
+  selectedPropertyIds: [],
+  currentStep: 'select_properties',
+  offerDraftId: null,
+  editableFields: {},
+  pdfPreviewReady: false,
+  messageDraft: '',
+  messageSubject: '',
+  attachments: [],
+  open: (needId, needTitle) =>
+    set({
+      isOpen: true,
+      selectedNeedId: needId,
+      needTitle,
+      selectedPropertyIds: [],
+      currentStep: 'select_properties',
+      offerDraftId: null,
+      editableFields: {},
+      pdfPreviewReady: false,
+      messageDraft: '',
+      messageSubject: '',
+      attachments: [],
+    }),
+  close: () => set({ isOpen: false }),
+  toggleProperty: (id) =>
+    set((s) => ({
+      selectedPropertyIds: s.selectedPropertyIds.includes(id)
+        ? s.selectedPropertyIds.filter((p) => p !== id)
+        : [...s.selectedPropertyIds, id],
+    })),
+  setSelectedProperties: (ids) => set({ selectedPropertyIds: ids }),
+  setStep: (currentStep) => set({ currentStep }),
+  setOfferDraftId: (id) => set({ offerDraftId: id }),
+  updateField: (fieldId, value) =>
+    set((s) => ({ editableFields: { ...s.editableFields, [fieldId]: value } })),
+  setPdfReady: () => set({ pdfPreviewReady: true }),
+  setMessageDraft: (messageDraft) => set({ messageDraft }),
+  setMessageSubject: (messageSubject) => set({ messageSubject }),
+  addAttachment: (a) => set((s) => ({ attachments: [...s.attachments, a] })),
+  removeAttachment: (id) =>
+    set((s) => ({ attachments: s.attachments.filter((a) => a.id !== id) })),
+  reset: () =>
+    set({
+      isOpen: false,
+      selectedNeedId: null,
+      needTitle: '',
+      selectedPropertyIds: [],
+      currentStep: 'select_properties',
+      offerDraftId: null,
+      editableFields: {},
+      pdfPreviewReady: false,
+      messageDraft: '',
+      messageSubject: '',
+      attachments: [],
+    }),
+}))