feat: merge Markt-Leads + Markt Intelligence → Marktchancen

Two-pane UX (from Market Intelligence) with supply-relevant data
(FutureSignal + portfolio property matches from Markt-Leads):
- Left pane: filterable signal list with probability badge + portfolio match count
- Right pane: company overview, KI-Analyse, market indicators, Faktencheck,
  portfolio matches (click → Meine Objekte), Reminder erstellen action
- No OPS-level actions (approve/reject/review stripped out)
- Nav: remove Markt-Leads entry, rename to Marktchancen

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

src/components/layout/appShellConfig.ts

@@ -3,7 +3,6 @@ import type { LucideIcon } from 'lucide-react'
 import {
   LayoutDashboard,
   Building2,
-  Target,
   CheckSquare,
   Search,
   List,
@@ -49,10 +48,9 @@ export const WORKSPACE_CONFIG: Record<WorkspaceType, WorkspaceConfig> = {
       { path: '/supply/dashboard', label: 'Übersicht', icon: LayoutDashboard },
       { path: '/supply/properties', label: 'Meine Objekte', icon: Building2 },
       { path: '/supply/reminder-manager', label: 'Reminder Manager', icon: BellRing },
-      { path: '/supply/market-leads', label: 'Markt-Leads', icon: Target },
       { path: '/supply/anfragen', label: 'Anfragencenter', icon: MessageSquare },
       { path: '/supply/data-quality', label: 'Datenpflege', icon: CheckSquare },
-      { path: '/supply/market-intelligence', label: 'Markt Intelligence', icon: Radar },
+      { path: '/supply/market-intelligence', label: 'Marktchancen', icon: Radar },
       { path: '/supply/my-listings', label: 'Inserate', icon: ClipboardList },
     ],
   },