devices: pool-of-spaces model — drop lane, per-relay direction

A parking lot is one pool of spaces with a flexible set of entry/exit
points — no "lane". Direction is a property of each RELAY inside an access
controller; readers/cameras bind to a controller relay and inherit it.

Schema:
- drop `lane` from ledger_events, device_events, sessions
- rename lane_devices -> devices (no lane/direction columns)
- access config.relays=[{relay,direction,button?}]; reader/camera
  config.controllerId+relay binding
- fresh 0000_baseline migration (history reset; dev data was throwaway)

Signed ledger:
- remove `lane` from canonicalize(); bump signer keyId sw-hmac-v1 -> v2
  (v1 events won't verify under v2 — intentional, gated per-event by keyId)

Server:
- new device-resolve.ts (replaces lane-map.ts): relayForButton,
  relayForDevice, firstRelayByDirection, devicesByDirection
- entry-flow: button terminal -> its relay; exit/permit: reader's bound
  relay; dispatcher resolves the bound relay + inherited direction
- camera snapshots fire by direction site-wide, async, never block open
- DeviceConfig widened to nested JSON for relays[]

Web:
- wizard: no lane selector; add controllers (relay map + entry-button
  terminal) first, then bind readers/cameras/printers to a controller relay

Wiki: new entry-exit-points.md (replaces lane-direction); reworked
entry-exit-readers, parking-session, first-run-setup, device-registry,
append-only-event-chain, device-events; removed stale lane/LaneMap mentions.

apps/server/src/exit-flow.ts

@@ -1,5 +1,7 @@
-import { and, eq, laneDevices, ledgerEvents, sessions, type Db } from "@parking/db";
+import { eq, ledgerEvents, sessions, type Db, type DeviceRow } from "@parking/db";
 import { registry, type AccessControlDevice } from "@parking/devices";
+import type { ResolvedRelay } from "./device-resolve.js";
+import { snapshotAsync } from "./snapshot.js";
 import type { LedgerPayload } from "@parking/shared";
 import type { FastifyBaseLogger } from "fastify";
 import type { DeviceReadEvent, ReadOutcome } from "./device-events.js";
@@ -25,7 +27,6 @@ import type { EventLog } from "./event-log.js";
 
 interface SessionView {
   readonly identity: string;
-  readonly lane: number;
   readonly enteredAt: string;
   readonly open: boolean; // no vehicle_exit yet
   readonly paidAt: string | null; // latest payment time, if any
@@ -44,23 +45,23 @@ export class ExitFlow {
     this.#logger = logger;
   }
 
-  /** Handle a transient-ticket read at a known exit lane (lane pre-resolved by the
-   *  read dispatcher, which has already ruled out a permit match). */
-  async handleAt(lane: number, e: DeviceReadEvent): Promise<ReadOutcome> {
+  /** 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). */
+  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" };
     this.#inFlight.add(key);
     try {
-      return await this.#runExit(lane, e);
+      return await this.#runExit(resolved, e);
     } catch (err) {
-      this.#logger.error(`exit-flow failed (lane ${lane}): ${(err as Error).message}`);
+      this.#logger.error(`exit-flow failed: ${(err as Error).message}`);
       return { accepted: false, reason: (err as Error).message };
     } finally {
       this.#inFlight.delete(key);
     }
   }
 
-  async #runExit(lane: number, e: DeviceReadEvent): Promise<ReadOutcome> {
+  async #runExit(resolved: ResolvedRelay, e: DeviceReadEvent): Promise<ReadOutcome> {
     const view = this.#sessionFor(e.value);
 
     // No matching open session — unknown/duplicate ticket. Reject + log.
@@ -68,11 +69,10 @@ export class ExitFlow {
       const reason = view ? "exit refused — session already closed" : "exit refused — no open session for credential";
       await this.#log.append({
         type: "anomaly",
-        lane,
         identity: e.value,
         payload: { reason, exitRefused: true },
       });
-      this.#logger.warn(`exit refused (lane ${lane}): no open session for ${e.value}`);
+      this.#logger.warn(`exit refused: no open session for ${e.value}`);
       return { accepted: false, direction: "exit", reason };
     }
 
@@ -89,30 +89,33 @@ export class ExitFlow {
         : "exit refused — walk-back grace expired (top-up required)";
       await this.#log.append({
         type: "anomaly",
-        lane,
         identity: e.value,
         payload: { reason, exitRefused: true, sessionRef: e.value },
       });
-      this.#logger.warn(`exit refused (lane ${lane}, ${e.value}): ${reason}`);
+      this.#logger.warn(`exit refused (${e.value}): ${reason}`);
       return { accepted: false, direction: "exit", reason };
     }
 
     // Valid: sign the exit BEFORE opening, then open, then update the cache.
     await this.#log.append({
       type: "vehicle_exit",
-      lane,
       direction: "exit",
       source: e.kind === "plate" ? "lpr" : "ticket",
       identity: e.value,
       payload: { sessionRef: e.value },
     });
 
-    const access = await this.#exitAccess(lane);
-    if (access) {
-      await access.pulseOpen(1); // exit barrier; door mapping is config-driven later
-    } else {
-      this.#logger.warn(`exit signed for ${e.value} but lane ${lane} has no access device to open`);
-    }
+    const access = this.#buildAccess(resolved.controller);
+    if (access) await access.pulseOpen(resolved.relay);
+    else this.#logger.warn(`exit signed for ${e.value} but the exit relay won't build`);
+
+    // SNAPSHOT — fire the exit camera(s), never awaited (evidence, not a gate).
+    void snapshotAsync({
+      db: this.#db,
+      direction: "exit",
+      identity: e.value,
+      logger: this.#logger,
+    }).catch((err) => this.#logger.error(`exit snapshot error: ${(err as Error).message}`));
 
     try {
       this.#db
@@ -152,7 +155,6 @@ export class ExitFlow {
 
     return {
       identity,
-      lane: entry.lane,
       enteredAt: entry.occurredAt,
       open: !exited,
       paidAt,
@@ -160,14 +162,8 @@ export class ExitFlow {
     };
   }
 
-  /** The lane's access device, to open the exit barrier. */
-  async #exitAccess(lane: number): Promise<AccessControlDevice | null> {
-    const row = await this.#db
-      .select()
-      .from(laneDevices)
-      .where(and(eq(laneDevices.category, "access"), eq(laneDevices.lane, lane)))
-      .get();
-    if (!row || !row.enabled) return null;
+  /** Build a live access adapter from a resolved controller row, or null. */
+  #buildAccess(row: DeviceRow): AccessControlDevice | null {
     const driver = registry.get(row.driverId);
     if (!driver) return null;
     try {