feat(entry): admin bypass of the presence gate for faulty radar/camera

The entry button (physical press AND the operator-issued mint) requires
radar/loop presence + camera detection to confirm a real vehicle. When one
of those devices is faulty, the gate blocks legitimate transient entry. Let
the ADMIN drop a specific signal as a requirement until support fixes the
hardware — the admin is not the adversary, but weakening an anti-fraud gate
stays attributed and auditable:

- Granular: bypass radar and camera independently (Setup → controller
  section). A dead camera drops only the camera check; a dead radar only
  radar. Both off = normal gate; both on = press-to-print.
- Signed: a DEDICATED endpoint (PUT /api/site-config/presence-bypass,
  site:update) appends a signed config_change {setting, value, prev,
  operator} per actually-changed signal — new ledger type. No-op toggles
  sign nothing; disabling signs too. Kept out of the generic site PUT.
- Flagged: every vehicle_entry issued (and every refusal anomaly) while
  bypassed carries presenceBypassed:[...] in its signed payload.
- Persists until turned off; amber warning in Setup while active. The
  booth entry light treats a bypassed signal as satisfied (server
  re-checks authoritatively). Physical-button path falls through to the
  cooldown backstop when radar is bypassed.
- Migration 0020: two boolean site_config columns (default off).

Fixes a latent bug surfaced by the tests: firstRelayByDirection returned no
presenceInput, so issueForOperator's radar gate always read "presence loop
unavailable" — operator-issue never actually gated on radar. The resolver
now attaches the presence input serving the relay (mirrors relayForButton).

10 new tests: 5 gate combinations (each bypass drops only its signal +
records it), 5 route tests (RBAC, signed transitions, no-op, validation).

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

apps/web/src/api.ts

@@ -1151,6 +1151,11 @@ export interface SiteConfig {
   reserveSubscriberSpots: boolean;
   /** Master switch for the ANPR subscriber-entry bridge (auto-open on a plate read). */
   anprEntryEnabled: boolean;
+  /** Entry presence-gate bypass: drop radar/loop as an entry-button requirement (faulty
+   *  device). Set only via the dedicated signed endpoint, not saveSiteConfig. */
+  bypassPresenceRadar: boolean;
+  /** Entry presence-gate bypass: drop camera detection as an entry-button requirement. */
+  bypassPresenceCamera: boolean;
   parkName: string | null;
   operatorName: string | null;
   /** NIUS — Albanian tax/identification number. */
@@ -1404,6 +1409,12 @@ export function fetchSiteConfig(): Promise<SiteConfig> {
 export function saveSiteConfig(patch: Partial<SiteConfig>): Promise<SiteConfig> {
   return apiFetch("/api/site-config", { method: "PUT", body: JSON.stringify(patch) });
 }
+
+/** Toggle the entry presence-gate bypass (radar/camera). Dedicated signed endpoint —
+ *  each changed signal appends a config_change to the ledger. See entry-presence-bypass. */
+export function updatePresenceBypass(patch: { radar?: boolean; camera?: boolean }): Promise<SiteConfig> {
+  return apiFetch("/api/site-config/presence-bypass", { method: "PUT", body: JSON.stringify(patch) });
+}
 export function setCapacity(capacity: number | null): Promise<SiteConfig> {
   return saveSiteConfig({ capacity });
 }