Add example environment configuration for MongoDB and OpenAI

Author: TheSonOfThomp

apps/chatbot-server/.env.example

@@ -0,0 +1,9 @@
+# MongoDB config
+MONGODB_CONNECTION_URI="<MongoDB connection URI with Atlas Vector Search configured on 'embedded_content'>"
+VECTOR_SEARCH_INDEX_NAME="vector_index" # or whatever your index name is
+MONGODB_DATABASE_NAME="mongodb-chatbot-framework-chatbot" # or whatever your database name is. must contain vector search index.
+
+# OpenAI config
+OPENAI_API_KEY=<OpenAI API key>
+OPENAI_EMBEDDING_MODEL="text-embedding-ada-002" # or other model
+OPENAI_CHAT_COMPLETION_MODEL="gpt-3.5-turbo" # or other model