inventory: barcode scanner in Add-item dialog

Add a camera barcode/QR scanner (components/scan/barcode-scanner.tsx,
@zxing/browser lazy-loaded) and a Barcode/NDC field to the pharmacy
Add-item dialog. Scanning a GS1 DataMatrix auto-fills expiry (AI 17) and
lot (AI 10 -> notes), with the GTIN (AI 01) as the barcode; plain 1D
barcodes drop straight into the field. Persists a nullable inventory
barcode column (migration 0036) through the type/validation/service, and
surfaces it on the item detail. i18n added to all locales.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/drizzle/meta/_journal.json

@@ -253,6 +253,13 @@
       "when": 1783530491321,
       "tag": "0035_slippery_retro_girl",
       "breakpoints": true
+    },
+    {
+      "idx": 36,
+      "version": "7",
+      "when": 1784406410448,
+      "tag": "0036_aspiring_expediter",
+      "breakpoints": true
     }
   ]
 }