feat(booth): badge subscriber out-of-window entries in the live feed

A subscriber entering outside their plan's allowed window gets a deferred
transient charge (windowOwedMinor, collected/gated at exit) — but it was
SILENT at the booth: the entry showed as a plain subscriber pass with no hint
money is owed, so the operator only discovers it at exit.

Surface it: add a "out-of-window — owes fee" badge on any entry/exit event
carrying windowOwedMinor > 0, so the operator sees immediately that this
subscriber owes a fee. Also type the window-charge fields on LedgerPayload
(were riding the open-ended index signature).

Behaviour is otherwise unchanged and correct — verified the live "Mon Kukaleshi"
entry: entered 20:29 local (before the 21:00 Mon–Sat window, grace 5m), owes
100 ALL for 18:29–18:55Z, stamped on the signed entry, still owed, gated at
exit. Subscribers get no ticket by design. Build+lint 12/12.

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

packages/shared/src/index.ts

@@ -287,6 +287,15 @@ export interface LedgerPayload {
   /** cash_in / cash_out voucher: a human-facing voucher number printed on the slip
    *  (Mandat Nr.). Sequential per type; signed for reproducibility. */
   readonly voucherNo?: string;
+  /** subscription tariff-bridge: an early-entry / late-exit transient charge OWED for
+   *  parking outside the plan's allowed window, stamped on the vehicle_entry and collected
+   *  (gated) at exit. The priced gap + tariff version travel alongside for reproducibility.
+   *  See wiki/entities/subscription.md ("tariff bridge"). */
+  readonly windowOwedMinor?: number;
+  readonly windowCurrency?: string;
+  readonly windowTariffVersionId?: string;
+  readonly windowGapStart?: string;
+  readonly windowGapEnd?: string;
   /** Free-form for forward-compat without a schema change. */
   readonly [k: string]: unknown;
 }