fix(exit): stuck active session — paid ticket with no vehicle_exit

A paid car that left via a manual barrier re-open kept no vehicle_exit, so
activeSessions() saw it as permanently open and the grace-expiry eviction
(which only ran for exited sessions) never fired — it lingered forever
(ticket T-397815c0).

- reopenBarrier() now signs a vehicle_exit (source:manual) when the session
  is still open, closing it; still no second exit when already exited
  (phantom re-close — no double-count).
- activeSessions() ages out a PAID open session past grace even with no exit
  (unpaid open sessions never age out — a car owing money stays). Pure
  display filter; the signed log is untouched.

Verified both fixes + chain integrity on a fresh DB. A one-off corrective
vehicle_exit was appended to the live ledger to clear T-397815c0.

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

apps/server/src/exit-flow.ts

@@ -170,10 +170,16 @@ export class ExitFlow {
    * opens the barrier with a signed trace.
    *
    * Guard: requires a PAYMENT — no payment, no re-open (the no-unpaid-bypass rule;
-   * the UI also hides the button). Unlike exitForBooth this does NOT sign a
-   * `vehicle_exit` (the session may already be exited; a second exit would
-   * double-count occupancy). It re-pulses the exit relay and signs an `anomaly`
+   * the UI also hides the button). It re-pulses the exit relay and signs an `anomaly`
    * ("manual barrier open", attributed). Idempotent-safe per identity via #inFlight.
+   *
+   * CLOSING THE SESSION (fix 2026-06-18): if the session is still OPEN (no
+   * `vehicle_exit` yet), the manual re-open *is* this car leaving — so we also sign a
+   * `vehicle_exit` (attributed as human-intervention). Without it the paid session
+   * would linger in the Active Sessions list FOREVER, since the grace-expiry eviction
+   * only applies to already-exited sessions (the T-397815c0 bug). If the session is
+   * already CLOSED (a prior exit exists — the phantom re-close case), we do NOT sign a
+   * second exit (that would double-count occupancy): anomaly only, as before.
    * See wiki/concepts/booth-exit-flow.md.
    */
   async reopenBarrier(identity: string, operator?: string): Promise<BoothReopenResult> {
@@ -195,7 +201,7 @@ export class ExitFlow {
     try {
       const resolved = firstRelayByDirection(this.#db, "exit");
       // Sign the audited anomaly FIRST (the intervention is recorded whether or not
-      // the physical open succeeds) — never a second vehicle_exit.
+      // the physical open succeeds).
       await this.#log.append({
         type: "anomaly",
         identity: id,
@@ -207,6 +213,16 @@ export class ExitFlow {
         },
       });
 
+      // Close an OPEN session: the re-open is the exit. Sign the vehicle_exit so the
+      // session leaves the active list + occupancy settles. Skip when already exited
+      // (no double-count). Recorded as a human-intervention exit for the audit trail.
+      if (view.open) {
+        await this.#signExit(id, "manual");
+        this.#closeSessionCache(id);
+        this.#fireExitSnapshot(id);
+        this.#logger.info(`barrier re-open also closed open session ${id} (human-intervention exit)`);
+      }
+
       if (!resolved) {
         this.#logger.warn(`barrier re-open for ${id}: no exit relay configured`);
         return { ok: true, opened: false, reason: "no exit barrier configured — open manually" };
@@ -230,7 +246,7 @@ export class ExitFlow {
   }
 
   /** Handle a transient-ticket read at an exit barrier (the relay pre-resolved by the
-   *  read dispatcher from the reader's binding, which has ruled out a permit match). */
+   *  read dispatcher from the reader's binding, which has ruled out a subscription match). */
   async handleAt(resolved: ResolvedRelay, e: DeviceReadEvent): Promise<ReadOutcome> {
     const key = `${e.deviceId}:${e.value}`;
     if (this.#inFlight.has(key)) return { accepted: false, reason: "duplicate read in flight" };
@@ -321,14 +337,19 @@ export class ExitFlow {
     return { accepted: true, direction: "exit" };
   }
 
-  /** Append the signed vehicle_exit. `source` defaults to "ticket" (booth/manual). */
-  async #signExit(identity: string, source: "ticket" | "lpr" = "ticket"): Promise<void> {
+  /** Append the signed vehicle_exit. `source`: "ticket" (booth/reader), "lpr" (plate),
+   *  or "manual" (a human-intervention barrier re-open that closes an open session —
+   *  see reopenBarrier). */
+  async #signExit(identity: string, source: "ticket" | "lpr" | "manual" = "ticket"): Promise<void> {
     await this.#log.append({
       type: "vehicle_exit",
       direction: "exit",
       source,
       identity,
-      payload: { sessionRef: identity },
+      payload: {
+        sessionRef: identity,
+        ...(source === "manual" ? { reason: "human-intervention exit (manual barrier open)" } : {}),
+      },
     });
   }