Remove UHPPOTE/ZKTeco; Dingtian is the only access driver

Neither UHPPOTE nor ZKTeco is used — the Dingtian relay controller was chosen
and verified. Remove their code and re-scope the wiki.

Code:
- delete access-uhppote.ts, uhppoted.d.ts, access.ts (zkteco/esp32-relay stubs),
  and the three uhppote-*.mjs hardware test scripts.
- remove the `uhppoted` npm dependency from @parking/devices and @parking/server.
- unregister uhppote/zkteco/esp32-relay from the driver registry; drop their
  exports. Catalog access drivers = dingtian only. Build green (5/5).
- refresh now-stale example comments (registry/interfaces/setup/api) to use
  current examples; keep the two "UHPPOTE blocker" references that explain why
  the precondition capability exists.

Wiki (kept pages, re-scoped):
- uhppote-controller, zkteco-controller -> rejected/historical with callouts;
  uhppote-vs-esp32 -> historical (detection-vs-prevention lens still useful).
- re-point all "current device" framing (standing-decisions, bom, overview,
  open-questions, device-registry, device-discovery, index) to dingtian-relay.
- transferable concepts (network-isolation, event-log-ingestion, barrier-not-a-
  door, threat-model) untouched. Raw source immutable. Links lint clean.

packages/devices/src/drivers/index.ts

@@ -2,9 +2,7 @@
 // module wires the catalog. Add a new device by registering it here.
 
 import { registry } from "../registry.js";
-import { esp32RelayDriver, zktecoDriver } from "./access.js";
 import { dingtianDriver } from "./access-dingtian.js";
-import { uhppoteDriver } from "./access-uhppote.js";
 import { dahuaDriver, hikvisionDriver } from "./camera.js";
 import { tcpipReaderDriver, wiegandReaderDriver } from "./reader.js";
 
@@ -14,10 +12,7 @@ let registered = false;
 export function registerBuiltinDrivers(): void {
   if (registered) return;
   registered = true;
-  registry.register(uhppoteDriver);
   registry.register(dingtianDriver);
-  registry.register(zktecoDriver);
-  registry.register(esp32RelayDriver);
   registry.register(wiegandReaderDriver);
   registry.register(tcpipReaderDriver);
   registry.register(hikvisionDriver);
@@ -25,10 +20,7 @@ export function registerBuiltinDrivers(): void {
 }
 
 export {
-  uhppoteDriver,
   dingtianDriver,
-  zktecoDriver,
-  esp32RelayDriver,
   wiegandReaderDriver,
   tcpipReaderDriver,
   hikvisionDriver,