feat: Implement Pinecone vector store integration

- Update config.py with Pinecone settings and model configurations
- Implement VectorStore class with Pinecone backend
- Add comprehensive vector operations (add, search, delete)
- Set up proper error handling and metadata management
- Add .gitignore for Python project

.env.example

@@ -0,0 +1,16 @@
+# API Keys
+COHERE_API_KEY=your_cohere_api_key_here
+
+# Model Settings
+MODEL_NAME=gpt2
+EMBEDDING_MODEL=embed-english-v3.0
+
+# Server Settings
+HOST=0.0.0.0
+PORT=8000
+DEBUG=True
+
+# Storage Settings
+VECTOR_STORE_PATH=data/vector_store
+PAST_CAMPAIGNS_PATH=data/past_campaigns
+USER_QUERIES_PATH=data/user_queries