Improve camera model search with per-model ranking and two-stage loading

- Split camera results into individual models (Brand: Model format)
- Add model-specific relevance scoring for better search results
- Implement two-stage autocomplete: 10 results immediately, 50 after 1 second
- Filter out "Other" models from search results
- Sort models by relevance score (exact matches first)
- Add auto.json brand for automatic detection fallback

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

data/brands/auto.json

@@ -0,0 +1,13 @@
+{
+  "brand": "Auto",
+  "brand_id": "auto",
+  "last_updated": "2025-01-01",
+  "source": "strix",
+  "website": "",
+  "cameras": [
+    {
+      "model": "Automatic Detection",
+      "entries": []
+    }
+  ]
+}