feat(berths): inline spec-PDF preview, manual-pin badge, maintenance module toggle, under-offer popover

Post-cutover UAT batch #3:
- #62 Spec tab renders the current berth spec PDF inline (lazy PdfViewer,
  toggleable, default-open) + explicit download. Interest Documents tab
  already previews/downloads linked deal docs inline (verified).
- #57 Surface berths.status_override_mode through the interest-berths API;
  linked-berth rows show an amber "Pin overrides pitch" badge + corrected
  consequence copy when a berth is specifically-pitched but manually pinned
  (the soft-pin wins on the public map).
- #63 New maintenance-module gate (maintenance_module_enabled, default on):
  registry + admin Settings toggle, maintenance-module.service, port-provider
  useMaintenanceModuleEnabled, layout wiring, buildBerthTabs hides the
  Maintenance tab when off, and both maintenance log routes assert the gate.
- #66 BerthOccupancyChip: >1 competing interest opens a popover listing every
  deal (name + stage + in-EOI/primary + link); single stays a direct link.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/app/(dashboard)/layout.tsx

@@ -20,6 +20,7 @@ import { getPortBrandingConfig } from '@/lib/services/port-config';
 import { isTenanciesModuleEnabled } from '@/lib/services/tenancies-module.service';
 import { isExpensesModuleEnabled } from '@/lib/services/expenses-module.service';
 import { isResidentialModuleEnabled } from '@/lib/services/residential-module.service';
+import { isMaintenanceModuleEnabled } from '@/lib/services/maintenance-module.service';
 
 export default async function DashboardLayout({ children }: { children: React.ReactNode }) {
   const headerList = await headers();
@@ -127,12 +128,29 @@ export default async function DashboardLayout({ children }: { children: React.Re
   const residentialModuleByPort: Record<string, boolean> =
     Object.fromEntries(residentialModuleEntries);
 
+  // Per-port maintenance-module gate. Defaults to enabled (registry
+  // default) so existing ports keep the berth Maintenance tab on deploy.
+  // Resolved server-side so the tab SSRs in/out without flicker.
+  const maintenanceModuleEntries = await Promise.all(
+    ports.map(async (p) => {
+      try {
+        return [p.id, await isMaintenanceModuleEnabled(p.id)] as const;
+      } catch {
+        // Conservative default on lookup failure: keep the feature visible.
+        return [p.id, true] as const;
+      }
+    }),
+  );
+  const maintenanceModuleByPort: Record<string, boolean> =
+    Object.fromEntries(maintenanceModuleEntries);
+
   return (
     <QueryProvider>
       <PortProvider
         ports={ports}
         defaultPortId={ports[0]?.id ?? null}
         tenanciesModuleByPort={tenanciesModuleByPort}
+        maintenanceModuleByPort={maintenanceModuleByPort}
       >
         <PermissionsProvider>
           <SocketProvider>