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

packages/db/drizzle/0020_entry_presence_bypass.sql

@@ -0,0 +1,12 @@
+-- Entry presence-gate bypass (2026-07-02). The operator-issued entry button (and the
+-- physical entry button) require a REAL vehicle at the barrier: radar/loop presence AND a
+-- camera vehicle-detection. When a device is FAULTY (dead radar, dead camera), that gate
+-- blocks legitimate transient entry. These flags let the ADMIN drop a specific signal as a
+-- requirement until support fixes the hardware. Granular on purpose: a faulty camera drops
+-- only the camera check (radar still gates); a faulty radar drops only radar. Both null/0 =
+-- the normal both-required gate. Enabling/disabling is ALSO signed into the ledger
+-- (config_change) — the admin is not the adversary, but weakening an anti-fraud gate stays
+-- attributed + auditable. See wiki/concepts/entry-presence-bypass.md.
+ALTER TABLE `site_config` ADD `bypass_presence_radar` integer DEFAULT 0 NOT NULL;
+--> statement-breakpoint
+ALTER TABLE `site_config` ADD `bypass_presence_camera` integer DEFAULT 0 NOT NULL;

packages/db/drizzle/meta/_journal.json

@@ -141,6 +141,13 @@
       "when": 1781886200000,
       "tag": "0019_operator_session_create",
       "breakpoints": true
+    },
+    {
+      "idx": 20,
+      "version": "6",
+      "when": 1781886300000,
+      "tag": "0020_entry_presence_bypass",
+      "breakpoints": true
     }
   ]
 }