feat: portal redesign, pricing catalog, partner-staff invites

- portal: new admin/ and partner/ surfaces with full component library
  (AppLauncher, Avatar, Badge, Card, Modal, Tabs, etc.), composables,
  layouts, partner-routing middleware, and supporting server APIs
- pricing: Price schema/module with operator CRUD, pricing.vue catalog UI,
  Subscription extended with cycle/currency/perSeatAmount/seats snapshots
  for stable MRR aggregation
- partner staff: User.partnerId, invite-partner-user DTO and flow,
  /partners/:slug/users endpoints, InvitePartnerUserModal, shared
  dezky-partner-staff Authentik group
- /me: partner-aware endpoint returning user + partner context so portal
  can route between end-user and partner-admin surfaces
- tenant: seats field for portfolio displays and future MRR calculations
- operator: pricing page, signed-out page, useMe/useToast composables,
  ToastStack

apps/portal/assets/styles/base.css

@@ -25,3 +25,12 @@ button {
 a {
   color: inherit;
 }
+
+::-webkit-scrollbar { width: 10px; height: 10px; }
+::-webkit-scrollbar-thumb { background: rgba(128, 128, 128, 0.25); border-radius: 6px; }
+::-webkit-scrollbar-track { background: transparent; }
+
+:focus-visible {
+  outline: 2px solid var(--signal);
+  outline-offset: 2px;
+}