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

packages/shared/src/index.ts

@@ -68,6 +68,29 @@ export const ADMIN_ROLE_ID = "admin";
 export type SubscriptionPeriod = "day" | "week" | "month";
 export const SUBSCRIPTION_PERIODS: readonly SubscriptionPeriod[] = ["day", "week", "month"];
 
+/** A subscriber's allowed parking window for a day-type, as minutes-from-local-midnight
+ *  (0–1439). The window is the interval [fromMin, toMin); `toMin <= fromMin` means it
+ *  WRAPS past midnight (e.g. 20:00→08:00 = a night window: 1200..480). `allDay` = the
+ *  whole day is allowed (no charge). An ABSENT day-window = no restriction (24/7) for
+ *  that day-type. */
+export interface DayWindow {
+  readonly allDay?: boolean;
+  readonly fromMin?: number; // window opens (minutes-of-day, local)
+  readonly toMin?: number; // window closes (minutes-of-day, local)
+}
+
+/** Composed allowed-time windows on a [[subscription]] plan. A scan OUTSIDE the window
+ *  is charged the transient tariff for the out-of-window minutes (the "tariff bridge").
+ *  null/absent timeframes on a plan = 24/7, no charge ever. Evaluated in the site tz. */
+export interface PlanTimeframes {
+  readonly weekday?: DayWindow; // Mon–Fri
+  readonly weekend?: DayWindow; // Sat–Sun
+  /** Tolerance (minutes) around the window edges before a charge applies. */
+  readonly graceMin?: number;
+  /** IANA tz the windows are wall-clock evaluated in (the site tz, captured at sale). */
+  readonly tz?: string;
+}
+
 /** One immutable VERSION of a subscription plan (admin-composed catalog; latest with
  *  effectiveFrom ≤ sale instant prices a sale — the tariff-version pattern). The
  *  operator SELLS from this catalog; they never type a price. */
@@ -80,6 +103,8 @@ export interface SubscriptionPlan {
   readonly currency: string;
   readonly effectiveFrom: string;
   readonly active: boolean;
+  /** Allowed-time windows (tariff bridge). null/absent = 24/7, no time charge. */
+  readonly timeframes?: PlanTimeframes | null;
   readonly createdBy?: string | null;
   readonly createdAt?: string;
 }
@@ -302,6 +327,9 @@ export const REASON_CODES = [
   "sub.refused.outOfWindow",
   "sub.refused.noSession",
   "sub.refused.atCapacity",
+  // a subscriber owes an out-of-window (early-entry / late-exit) transient charge and
+  // hasn't paid it — exit is gated until they settle (the tariff-bridge gate).
+  "sub.refused.unpaidWindow",
 ] as const;
 
 export type ReasonCode = (typeof REASON_CODES)[number];
@@ -329,6 +357,7 @@ export const REASON_EN: Record<ReasonCode, string> = {
   "sub.refused.outOfWindow": "subscription refused — {status}/out-of-window",
   "sub.refused.noSession": "subscription exit with no open session (already out / never entered)",
   "sub.refused.atCapacity": "subscription refused — at capacity ({inUse}/{max} cars in)",
+  "sub.refused.unpaidWindow": "exit refused — out-of-window charge unpaid ({amount} {currency} owed); pay at the booth",
 };
 
 /**
@@ -1042,6 +1071,72 @@ export function localBreakdown(instantMs: number, tz: string): WallClock {
   };
 }
 
+// --- Subscription plan timeframes — the "tariff bridge" gap (pure, tz-aware) -------
+
+/** Is a day-of-week a weekend (Sat/Sun)? */
+function isWeekend(dow: number): boolean {
+  return dow === 0 || dow === 6;
+}
+
+/** Minute-of-day is inside the window [fromMin, toMin)? A window with toMin ≤ fromMin
+ *  WRAPS past midnight (night window 20:00→08:00 ⇒ in = m ≥ 1200 OR m < 480). */
+function inWindow(m: number, fromMin: number, toMin: number): boolean {
+  return toMin <= fromMin ? m >= fromMin || m < toMin : m >= fromMin && m < toMin;
+}
+
+/**
+ * The out-of-window GAP for a subscriber scan, or null when the scan is in-window (or
+ * the plan/day is unrestricted/all-day). This is the portion charged at the transient
+ * tariff (the "tariff bridge"):
+ *   - edge "entry" (early arrival): gap = [scan, next window-OPEN] — they pay transient
+ *     from arrival until their window starts (a 09:00 arrival to a 20:00 night window
+ *     owes 09:00→20:00, capped by the tariff's daily cap).
+ *   - edge "exit" (late departure): gap = [last window-CLOSE, scan] — they pay transient
+ *     from when their window ended until they actually leave (08:00→08:45).
+ * Grace widens the allowed window by `graceMin` on the relevant edge. Pure + tz-aware
+ * (wall-clock in `timeframes.tz` or the passed `tz`). Minutes-of-day arithmetic anchored
+ * on the scan's own local day keeps it DST-robust for the short gaps involved.
+ */
+export function outOfWindowGap(
+  timeframes: PlanTimeframes | null | undefined,
+  tz: string,
+  atISO: string,
+  edge: "entry" | "exit",
+): { start: string; end: string; minutes: number } | null {
+  if (!timeframes) return null;
+  const atMs = Date.parse(atISO);
+  if (Number.isNaN(atMs)) return null;
+  const zone = timeframes.tz || tz;
+  const wall = localBreakdown(atMs, zone);
+  const day: DayWindow | undefined = isWeekend(wall.dow) ? timeframes.weekend : timeframes.weekday;
+  // No window for this day-type, or explicitly all-day ⇒ unrestricted, no charge.
+  if (!day || day.allDay) return null;
+  if (typeof day.fromMin !== "number" || typeof day.toMin !== "number") return null;
+
+  const grace = Math.max(0, timeframes.graceMin ?? 0);
+  const nowMin = wall.hour * 60 + wall.minute;
+
+  if (inWindow(nowMin, day.fromMin, day.toMin)) return null; // already allowed
+
+  // Minutes (always ≥ 0) until the window OPENS, measured forward from the scan.
+  const minsUntil = (target: number) => ((target - nowMin) % 1440 + 1440) % 1440;
+  // Minutes (always ≥ 0) since the window CLOSED, measured backward from the scan.
+  const minsSince = (target: number) => ((nowMin - target) % 1440 + 1440) % 1440;
+
+  if (edge === "entry") {
+    // Early: charge from the scan until the window opens (minus grace tolerance).
+    let mins = minsUntil(day.fromMin) - grace;
+    if (mins <= 0) return null; // within grace of opening
+    const end = new Date(atMs + mins * 60_000).toISOString();
+    return { start: atISO, end, minutes: mins };
+  }
+  // Late exit: charge from when the window closed (plus grace) until the scan.
+  let mins = minsSince(day.toMin) - grace;
+  if (mins <= 0) return null; // within grace of closing
+  const start = new Date(atMs - mins * 60_000).toISOString();
+  return { start, end: atISO, minutes: mins };
+}
+
 /** "HH:MM" → minutes-of-day (0-1439). Invalid → NaN (validation rejects those). */
 function hourToMin(hhmm: string): number {
   const m = /^(\d{2}):(\d{2})$/.exec(hhmm);