feat: implement consolidation approval process for shared-wagon bookings

- Add migration for consolidation approvals table and status enum
- Create ConsolidationApprovalService to handle approval logic
- Implement repository for managing consolidation approvals
- Add entity for consolidation approval with necessary fields
- Develop frontend components for displaying and managing consolidation approvals
- Create tests for consolidation approval service to ensure correct behavior

apps/edr-freight-web/backoffice/src/components/layout/sidebar-sections.tsx

@@ -12,6 +12,7 @@ import {
   Image as ImageIcon,
   LayoutDashboard,
   LayoutGrid,
+  Link2,
   MapPin,
   Network,
   Package,
@@ -95,6 +96,14 @@ export const buildSidebarSections = (
           icon: <FileText />,
           permission: FREIGHT_PERMS.bookings.view,
         },
+        // Shared-wagon gate: a consolidated pair waits for a human decision
+        // before either half reaches Operations.
+        {
+          label: "Shared wagon approvals",
+          href: "/dashboard/consolidation-approvals",
+          icon: <Link2 />,
+          permission: FREIGHT_PERMS.bookings.approveConsolidation,
+        },
         {
           label: "Wagon cancellations",
           href: "/dashboard/wagon-cancellations",