feat(platform): residential module + admin UI + reliability fixes

Residential platform
- New schema: residentialClients, residentialInterests (separate from
  marina/yacht clients) with migration 0010
- Service layer with CRUD + audit + sockets + per-port portal toggle
- v1 + public API routes (/api/v1/residential/*, /api/public/residential-inquiries)
- List + detail pages with inline editing for clients and interests
- Per-user residentialAccess toggle on userPortRoles (migration 0011)
- Permission keys: residential_clients, residential_interests
- Sidebar nav + role form integration
- Smoke spec covering page loads, UI create flow, public endpoint

Admin & shared UI
- Admin → Forms (form templates CRUD) with validators + service
- Notification preferences page (in-app + email per type)
- Email composition + accounts list + threads view
- Branded auth shell shared across CRM + portal auth surfaces
- Inline editing extended to yacht/company/interest detail pages
- InlineTagEditor + per-entity tags endpoints (yachts, companies)
- Notes service polymorphic across clients/interests/yachts/companies
- Client list columns: yachtCount + companyCount badges
- Reservation file-download via presigned URL (replaces stale <a href>)

Route handler refactor
- Extracted yachts/companies/berths reservation handlers to sibling
  handlers.ts files (Next.js 15 route.ts only allows specific exports)

Reliability fixes
- apiFetch double-stringify bug fixed across 13 components
  (apiFetch already JSON.stringifies its body; passing a stringified
  body produced double-encoded JSON which failed zod validation)
- SocketProvider gated behind useSyncExternalStore-based mount check
  to avoid useSession() SSR crashes under React 19 + Next 15
- apiFetch falls back to URL-pathname → port-id resolution when the
  Zustand store hasn't hydrated yet (fresh contexts, e2e tests)
- CRM invite flow (schema, service, route, email, dev script)
- Dashboard route → [portSlug]/dashboard/page.tsx + redirect
- Document the dev-server restart-after-migration gotcha in CLAUDE.md

Tests
- 5-case residential smoke spec
- Integration test updates for new service signatures

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/components/admin/settings/settings-manager.tsx

@@ -30,6 +30,14 @@ const KNOWN_SETTINGS: Array<{
   type: 'boolean' | 'number' | 'json' | 'string';
   defaultValue: unknown;
 }> = [
+  {
+    key: 'client_portal_enabled',
+    label: 'Client Portal',
+    description:
+      'Allow clients of this port to sign in and manage their account through the client portal.',
+    type: 'boolean',
+    defaultValue: true,
+  },
   {
     key: 'ai_interest_scoring',
     label: 'AI Interest Scoring',
@@ -89,6 +97,14 @@ const KNOWN_SETTINGS: Array<{
     type: 'json',
     defaultValue: [],
   },
+  {
+    key: 'residential_notification_recipients',
+    label: 'Residential Notification Recipients',
+    description:
+      'Email addresses (JSON array) that receive sales alerts for new residential inquiries. Falls back to Inquiry Contact Email when empty.',
+    type: 'json',
+    defaultValue: [],
+  },
 ];
 
 export function SettingsManager() {