refactor(emex): rewrite EMEX integration, add category fallback

Replace browser-based Puppeteer scraper with standalone scraper wrapper.
Add EMEX as fallback source for categories when PL24 is unavailable.
Update vehicle decoding to use new synchronous EMEX API.

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

package.json

@@ -19,7 +19,11 @@
       "@nestjs/core",
       "esbuild",
       "msgpackr-extract",
+      "puppeteer",
       "sharp"
     ]
+  },
+  "dependencies": {
+    "puppeteer": "^23.11.1"
   }
 }