feat: transaction categorization UX improvements and description matching

Add journal entry preview, human-readable account names, auto-apply VAT,
fallback template suggestions, example prompts, invoice match comparison,
and batch result feedback. Also includes user-description-match extension,
describe/batch-describe API routes, improved AI categorization with multi-
suggestion support, and template embedding search.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

tsconfig.json

@@ -20,7 +20,8 @@
     ],
     "paths": {
       "@/*": ["./*"]
-    }
+    },
+    "types": ["vitest/globals"]
   },
   "include": [
     "next-env.d.ts",