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

apps/server/src/anpr-entry.test.ts

@@ -84,6 +84,7 @@ function fakeVision(opts: { enabled?: boolean; plate?: string; confidence?: numb
           plate: { text: opts.plate, confidence: opts.confidence ?? 0.99 },
           plates: [],
           lowConfidence: false,
+          vehicle: null,
           modelVersion: "test",
           tookMs: 1,
         };
@@ -177,6 +178,7 @@ describe("AnprBridge", () => {
         plate: { text: "AA111BB", confidence: confs[Math.min(i++, confs.length - 1)] },
         plates: [],
         lowConfidence: false,
+        vehicle: null,
         modelVersion: "test",
         tookMs: 1,
       })),
@@ -207,6 +209,7 @@ describe("AnprBridge", () => {
         plate: { text: "AA111BB", confidence: confs[Math.min(i++, confs.length - 1)] },
         plates: [],
         lowConfidence: false,
+        vehicle: null,
         modelVersion: "test",
         tookMs: 1,
       })),