feat(carwash): advisory vehicle category from the entry camera — mapping, pre-select, downgrade flag

The app plumbing for venue-modules.md §"Vehicle category from vision"; the model is the
open half (no bundled recognizer emits body_type yet, so the desk shows nothing until
phase A lands in the vision service).

- Shared: VEHICLE_CLASSES vocabulary, VehicleRead, CARWASH_VISION_THRESHOLD_DEFAULT,
  reason code carwash.categoryDowngrade; settings/order/lookup views carry the read.
- Vision contract: /analyze vehicle.body_type + confidence (service schema); the Node
  client normalises to the vocabulary and drops the rest.
- Record: snapshot.ts stores the read in the plate's device_events row (or its own when
  the plate was unreadable); vehicleForIdentity() resolves it like the plate.
- Car wash: carwash_categories.vision_classes (site mapping "car, sedan → Vetura"),
  carwash_config.vision_threshold (signed config_change when it moves), four vision
  columns on orders — migration 0030. Lookup returns vision + suggestedCategoryId.
- Desk pre-selects the mapped category and shows the read + snapshot thumbnail; Setup
  offers class chips per category and the threshold. Operator decides.
- Flag: a read at/above the threshold whose mapped category prices HIGHER than the chosen
  one signs one `anomaly` (both categories/prices, operator, snapshot) and stores its id on
  the order. Equal/upgrade/unsure/unmapped → nothing. Recorded only, never blocks, no
  reason prompt (user, 2026-09-06).

Tests in carwash.test.ts; wiki venue-modules (As built), opencv-anpr-service, log.

Claude-Session: https://claude.ai/code/session_01FWncR69HgGPuei1dLrW3cU

packages/db/src/schema.ts

@@ -1,5 +1,5 @@
 import { sql } from "drizzle-orm";
-import { blob, integer, primaryKey, sqliteTable, text, unique } from "drizzle-orm/sqlite-core";
+import { blob, integer, primaryKey, real, sqliteTable, text, unique } from "drizzle-orm/sqlite-core";
 
 // Schema notes:
 // - TWO event streams, deliberately separate (see wiki/decisions/event-streams-split.md):
@@ -653,6 +653,9 @@ export const carwashCategories = sqliteTable("carwash_categories", {
   name: text("name").notNull(),
   sortOrder: integer("sort_order").notNull().default(0),
   active: integer("active", { mode: "boolean" }).notNull().default(true),
+  /** The vision vocabulary classes this category covers (JSON array of VehicleClass) —
+   *  the site's own mapping ("car, sedan → Vetura"). Empty = never suggested by vision. */
+  visionClasses: text("vision_classes", { mode: "json" }).$type<string[]>().notNull().default(sql`'[]'`),
   createdAt: text("created_at")
     .notNull()
     .default(sql`(current_timestamp)`),
@@ -723,6 +726,13 @@ export const carwashOrders = sqliteTable("carwash_orders", {
   voidAt: text("void_at"),
   voidBy: text("void_by"),
   voidReason: text("void_reason"),
+  // Vision, advisory (venue-modules.md §Vehicle category): what the camera saw at entry,
+  // the category the site mapping suggested, and the `anomaly` signed when the operator
+  // chose a cheaper category above the confidence threshold. Never a tariff input.
+  visionClass: text("vision_class"),
+  visionConfidence: real("vision_confidence"),
+  visionCategoryId: text("vision_category_id"),
+  downgradeEventId: text("downgrade_event_id"),
 });
 
 /** Module-level settings singleton (id = 1). `payAt`: where wash money is taken at this
@@ -730,6 +740,8 @@ export const carwashOrders = sqliteTable("carwash_orders", {
 export const carwashConfig = sqliteTable("carwash_config", {
   id: integer("id").primaryKey(),
   payAt: text("pay_at", { enum: ["booth", "bay"] }).notNull().default("booth"),
+  /** Confidence floor (0–1) for a vision class to flag a category downgrade. */
+  visionThreshold: real("vision_threshold").notNull().default(0.8),
   updatedAt: text("updated_at"),
   updatedBy: text("updated_by"),
 });