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/lib/i18n/en.ts

@@ -46,6 +46,7 @@ export const en: Catalog = {
     tariff: "Tariff",
     tariffLab: "Tariff Lab",
     subscriptions: "Subscriptions",
+    plans: "Plans",
     site: "Site",
     users: "Users",
     roles: "Roles",
@@ -382,9 +383,15 @@ export const en: Catalog = {
     cred: "cred",
     plates: "{{count}} plate(s)",
     noPrice: "no price",
+    perDay: "day",
+    perWeek: "week",
     perMonth: "month",
-    monthlyPrice: "Monthly price",
-    pricePlaceholder: "e.g. 10000",
+    plan: "Plan",
+    planNone: "— comp / no charge —",
+    planNoneAvail: "No plans defined — an admin must create one first.",
+    quoting: "pricing…",
+    quotePrompt: "pick an end date",
+    quoteLine: "{{periods}} × {{unit}} · {{amount}} {{currency}}",
     tender: "Paid by",
     tenderCash: "Cash",
     tenderCard: "Card",
@@ -404,11 +411,7 @@ export const en: Catalog = {
     limitCarsInAtOnce: "limit cars in at once",
     validFrom: "Valid from",
     validTo: "Valid to",
-    months: "Months",
-    monthsHint: "months paid",
-    coverageHint: "until {{end}}",
-    totalDue: "total {{total}}",
-    validToOverride: "Valid to (manual)",
+    validToEnd: "Valid to (end)",
     isoDateOptional: "ISO date (optional)",
     boundPlates: "Bound plates",
     commaSeparatedOptional: "comma-separated (optional)",
@@ -441,6 +444,29 @@ export const en: Catalog = {
     statusSuspended: "suspended",
     statusRevoked: "revoked",
   },
+  plans: {
+    title: "Subscription plans",
+    intro: "Admin-defined plans the operator sells from — the price is looked up, never typed. Editing a plan publishes a new version; past sales keep their recorded price.",
+    add: "+ Add plan",
+    noneYet: "No plans yet. Add one so the booth can sell subscriptions.",
+    colName: "Name",
+    colPrice: "Price",
+    colEffective: "Effective",
+    inForce: "in force",
+    retired: "retired",
+    newVersion: "New version",
+    retire: "Retire",
+    newTitle: "New plan",
+    newVersionTitle: "Publish new version",
+    newVersionHint: "This publishes a NEW version of the plan — existing sales keep their original price.",
+    period: "Period",
+    pricePer: "Price per period",
+    namePlaceholder: "e.g. Hotel daily",
+    needName: "A plan name is required.",
+    needPrice: "Enter a price greater than zero.",
+    saved: "Plan saved.",
+    confirmRetire: "Retire the plan “{{name}}”? It will no longer be sellable (history is kept).",
+  },
   site: {
     occupancy: "Occupancy:",
     noCapacitySet: "(no capacity set)",