feat(mileage): add brand multi-select filter and customer fuzzy search

- Add brand multi-select filter (BatchMultiSelect) with 17 brand options
- Replace customer select with SearchableSelect for fuzzy search
- Server-side: add brand to vehicle-info SQL, cache, filters, and monitoring
- Customer filter now uses case-insensitive includes match on server side
- Add brand column to fullscreen table header and body
- Mobile-adaptive: compact inputs, constrained widths, scrollable dropdowns
- Bump version to 1.1.8

package.json

@@ -1,7 +1,7 @@
 {
   "name": "ln-bi",
   "private": true,
-  "version": "1.1.7",
+  "version": "1.1.8",
   "type": "module",
   "scripts": {
     "dev": "concurrently -n server,client -c blue,green \"npm run dev:server\" \"npm run dev:client\"",