Add Groq AI provider support

- Add groq-sdk dependency to backend
- Add groq_api_key and groq_model columns to users table
- Implement extractWithGroq, verifyWithGroq, verifyStockStatusWithGroq, arbitrateWithGroq functions
- Add Groq settings to backend routes with test endpoint
- Add Groq provider option to frontend Settings UI with model selection
- Support for llama-3.3-70b-versatile, llama-3.1-8b-instant, mixtral-8x7b-32768, gemma2-9b-it models

Resolves: #26

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

frontend/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "priceghost-frontend",
-  "version": "1.0.2",
+  "version": "1.0.6",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "priceghost-frontend",
-      "version": "1.0.2",
+      "version": "1.0.6",
       "dependencies": {
         "axios": "^1.6.0",
         "react": "^18.2.0",