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.

packages/db/drizzle/meta/0000_snapshot.json

@@ -1,7 +1,7 @@
 {
   "version": "6",
   "dialect": "sqlite",
-  "id": "cd09c11f-4306-4ac8-a335-7c050d080ab6",
+  "id": "a6d81d46-c4a4-4ee7-8565-ec012bbe0252",
   "prevId": "00000000-0000-0000-0000-000000000000",
   "tables": {
     "blocklist": {
@@ -82,13 +82,6 @@
           "notNull": false,
           "autoincrement": false
         },
-        "lane": {
-          "name": "lane",
-          "type": "integer",
-          "primaryKey": false,
-          "notNull": false,
-          "autoincrement": false
-        },
         "category": {
           "name": "category",
           "type": "text",
@@ -125,8 +118,8 @@
       "uniqueConstraints": {},
       "checkConstraints": {}
     },
-    "lane_devices": {
-      "name": "lane_devices",
+    "devices": {
+      "name": "devices",
       "columns": {
         "id": {
           "name": "id",
@@ -135,13 +128,6 @@
           "notNull": true,
           "autoincrement": false
         },
-        "lane": {
-          "name": "lane",
-          "type": "integer",
-          "primaryKey": false,
-          "notNull": true,
-          "autoincrement": false
-        },
         "category": {
           "name": "category",
           "type": "text",
@@ -217,13 +203,6 @@
           "notNull": false,
           "autoincrement": false
         },
-        "lane": {
-          "name": "lane",
-          "type": "integer",
-          "primaryKey": false,
-          "notNull": true,
-          "autoincrement": false
-        },
         "source": {
           "name": "source",
           "type": "text",
@@ -436,13 +415,6 @@
           "notNull": true,
           "autoincrement": false
         },
-        "lane": {
-          "name": "lane",
-          "type": "integer",
-          "primaryKey": false,
-          "notNull": false,
-          "autoincrement": false
-        },
         "identity": {
           "name": "identity",
           "type": "text",
@@ -524,6 +496,97 @@
       "uniqueConstraints": {},
       "checkConstraints": {}
     },
+    "site_config": {
+      "name": "site_config",
+      "columns": {
+        "id": {
+          "name": "id",
+          "type": "integer",
+          "primaryKey": true,
+          "notNull": true,
+          "autoincrement": false
+        },
+        "capacity": {
+          "name": "capacity",
+          "type": "integer",
+          "primaryKey": false,
+          "notNull": false,
+          "autoincrement": false
+        },
+        "updated_at": {
+          "name": "updated_at",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": true,
+          "autoincrement": false,
+          "default": "(current_timestamp)"
+        }
+      },
+      "indexes": {},
+      "foreignKeys": {},
+      "compositePrimaryKeys": {},
+      "uniqueConstraints": {},
+      "checkConstraints": {}
+    },
+    "snapshots": {
+      "name": "snapshots",
+      "columns": {
+        "id": {
+          "name": "id",
+          "type": "text",
+          "primaryKey": true,
+          "notNull": true,
+          "autoincrement": false
+        },
+        "direction": {
+          "name": "direction",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": true,
+          "autoincrement": false
+        },
+        "device_id": {
+          "name": "device_id",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": false,
+          "autoincrement": false
+        },
+        "identity": {
+          "name": "identity",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": false,
+          "autoincrement": false
+        },
+        "content_type": {
+          "name": "content_type",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": true,
+          "autoincrement": false
+        },
+        "bytes": {
+          "name": "bytes",
+          "type": "blob",
+          "primaryKey": false,
+          "notNull": true,
+          "autoincrement": false
+        },
+        "captured_at": {
+          "name": "captured_at",
+          "type": "text",
+          "primaryKey": false,
+          "notNull": true,
+          "autoincrement": false
+        }
+      },
+      "indexes": {},
+      "foreignKeys": {},
+      "compositePrimaryKeys": {},
+      "uniqueConstraints": {},
+      "checkConstraints": {}
+    },
     "tariff_versions": {
       "name": "tariff_versions",
       "columns": {