feat: subscription plan catalog — config-defined pricing, dated spans, no typed amounts

Re-model subscription pricing from per-row, operator-typed prices into an
admin-composed, versioned PLAN CATALOG (the tariff pattern). The operator now
SELLS by picking a plan over a date span; the price is LOOKED UP, never typed —
removing the fat-finger risk on a money field — and day/week/month periods make
the hotel "guest stays 1–N days" case a daily plan over a check-in→check-out span.

- Schema/migration 0010: new `subscription_plans` (immutable, effective-dated,
  keyed by a stable planId; period day/week/month + per-period price + active
  flag). `subscriptions` gains planId/planVersionId; period enum widened. Seeds a
  "Monthly" plan from the existing site default price (no data loss).
- Pricing (pure, unit-tested in @parking/shared): periods = ceil(span / period),
  amount = periods × per-period price. Ceil = any started period is full (hotel
  practice). `resolvePlanVersion` picks the latest active version ≤ sale instant.
- Backend: new admin-only plan CRUD (`subscription:plan` permission); reworked
  sell path derives the amount from the plan; `POST /api/subscriptions/quote`
  returns a server-computed quote so the operator can't override it. The
  signed-payment sale fix is unchanged — only the amount SOURCE moved; payload
  now carries planId/planVersionId/periods. Updates never re-sell (price frozen).
- Frontend: SubscriptionManager sell form swaps the price field for a plan
  picker + start/end dates + a live quote line. New SubscriptionPlansManager
  (Setup tab) for the admin catalog. i18n (sq+en) for both.

Verified on a copy of the live DB: 0010 applies (existing subs intact), a
3-night hotel sale prices to 2,400 ALL, appends one signed payment with
planVersionId, chain verifies. Build+lint 12/12; 68 shared tests pass.

Claude-Session: https://claude.ai/code/session_01Xcm6ikLgGoCxxHrxtjkk5V

apps/web/src/router.tsx

@@ -23,6 +23,7 @@ import { SetupWizard } from "./SetupWizard.js";
 import { TariffComposer } from "./TariffComposer.js";
 import { TariffLab } from "./TariffLab.js";
 import { SubscriptionManager } from "./SubscriptionManager.js";
+import { SubscriptionPlansManager } from "./SubscriptionPlansManager.js";
 import { ShiftControl } from "./ShiftControl.js";
 import { SiteSettings } from "./SiteSettings.js";
 import { UsersManager } from "./UsersManager.js";
@@ -83,6 +84,7 @@ function SetupLayout() {
         {show("tariff:read") && <SetupTab to="/setup/tariff" label={t("nav.tariff")} />}
         {show("tariff:read") && <SetupTab to="/setup/tariff-lab" label={t("nav.tariffLab")} />}
         {show("subscription:read") && <SetupTab to="/setup/subscriptions" label={t("nav.subscriptions")} />}
+        {show("subscription:plan") && <SetupTab to="/setup/plans" label={t("nav.plans")} />}
         {show("site:read") && <SetupTab to="/setup/site" label={t("nav.site")} />}
         {show("user:read") && <SetupTab to="/setup/users" label={t("nav.users")} />}
         {show("role:read") && <SetupTab to="/setup/roles" label={t("nav.roles")} />}
@@ -410,6 +412,12 @@ const subscriptionsRoute = createRoute({
   beforeLoad: ({ context }) => requirePerm("subscription:read")(context),
   component: () => <SubscriptionManager />,
 });
+const subscriptionPlansRoute = createRoute({
+  getParentRoute: () => setupRoute,
+  path: "plans",
+  beforeLoad: ({ context }) => requirePerm("subscription:plan")(context),
+  component: () => <SubscriptionPlansManager />,
+});
 const siteRoute = createRoute({
   getParentRoute: () => setupRoute,
   path: "site",
@@ -467,6 +475,7 @@ const routeTree = rootRoute.addChildren([
     tariffRoute,
     tariffLabRoute,
     subscriptionsRoute,
+    subscriptionPlansRoute,
     siteRoute,
     usersRoute,
     rolesRoute,