feat: subscription v2 — quantity pricing, plan timeframes (tariff bridge), reserved spots

Three subscriber enhancements driven by real scenarios (migration 0011, all
additive columns — backward-compatible).

1. QUANTITY. One subscription covers N cars (a family pays once for two). Sale
   amount = span price × quantity; maxConcurrent defaults to the quantity so all
   N cars can be inside. Quantity rides in the payment payload.

2. PLAN TIMEFRAMES → TARIFF BRIDGE. A plan may restrict WHEN a subscriber may
   park (e.g. weekday 20:00→08:00, weekend all-day). A scan outside the window is
   NOT refused — the out-of-window minutes are charged at the normal TRANSIENT
   tariff (the subscriber is a transient for that time):
     - early entry: arrival → window-open, DEFERRED (signed as windowOwedMinor on
       the vehicle_entry payload), collected at exit;
     - late exit: window-close → departure, and exit is GATED
       (sub.refused.unpaidWindow) until paid at the booth.
   Pure, tz-aware outOfWindowGap in @parking/shared (12 unit tests); pricing
   reuses computeFee + the active tariff version
   (apps/server/src/subscription-window.ts). The exit refusal is a host-ONLINE
   business gate — the fail-open rule still governs the offline path.

3. RESERVED SPOTS. Site toggle reserve_subscriber_spots: occupancy holds
   max(0, quantity − itsCarsInside) per active subscription, so transients see
   "full" sooner; effectiveFree = capacity − count − reserved. Subscribers are
   never gated by full.

UI: quantity field + ×N quote (SubscriptionManager); timeframes editor
(SubscriptionPlansManager); reserve checkbox (SiteSettings); booth pay modal
shows an "OUT-OF-WINDOW" charge and takes payment to clear the exit gate.

Verified on a copy of the live DB: qty 2 = 2× price; a night-plan 19:30 entry →
30min/15,000 ALL owed, stamped + paid → gate clears, chain verifies; the reserve
toggle holds a qty-2 sub's 2 spots. Build+lint 12/12; 80 shared tests pass.

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

apps/server/src/routes/site.ts

@@ -29,6 +29,9 @@ interface SiteConfigBody extends Partial<Record<TextField, string | null>> {
   exitVoucherDefault?: boolean;
   /** Site default monthly subscription price in minor units (pre-fills the form). */
   subscriptionMonthlyPriceMinor?: number | null;
+  /** Reserve a spot in occupancy for each active subscriber's car(s), even when not
+   *  parked — so transients see "full" sooner and the subscriber's spot is held. */
+  reserveSubscriberSpots?: boolean;
 }
 
 /** Shape returned by GET/PUT: capacity + the booth flag + the subscription default
@@ -37,6 +40,7 @@ type SiteConfig = {
   capacity: number | null;
   exitVoucherDefault: boolean;
   subscriptionMonthlyPriceMinor: number | null;
+  reserveSubscriberSpots: boolean;
 } & Record<TextField, string | null>;
 
 function toSiteConfig(row: typeof siteConfig.$inferSelect | undefined): SiteConfig {
@@ -44,6 +48,7 @@ function toSiteConfig(row: typeof siteConfig.$inferSelect | undefined): SiteConf
     capacity: row?.capacity ?? null,
     exitVoucherDefault: row?.exitVoucherDefault ?? false,
     subscriptionMonthlyPriceMinor: row?.subscriptionMonthlyPriceMinor ?? null,
+    reserveSubscriberSpots: row?.reserveSubscriberSpots ?? false,
   } as SiteConfig;
   for (const f of TEXT_FIELDS) out[f] = row?.[f] ?? null;
   return out;
@@ -95,6 +100,12 @@ export async function siteRoutes(app: FastifyInstance, db: Db): Promise<void> {
       }
       patch.subscriptionMonthlyPriceMinor = p ?? null;
     }
+    if ("reserveSubscriberSpots" in body) {
+      if (typeof body.reserveSubscriberSpots !== "boolean") {
+        return reply.code(400).send({ error: "reserveSubscriberSpots must be a boolean" });
+      }
+      patch.reserveSubscriberSpots = body.reserveSubscriberSpots;
+    }
     for (const f of TEXT_FIELDS) {
       if (f in body) patch[f] = normText(body[f]);
     }