Recommend Sonnet 3.5 over Opus in select-model.md (#1611)

Author: dandv

docs/docs/setup/select-model.md

@@ -32,7 +32,7 @@ _You can also use other open-source chat models by adding them to your `config.j
 
 #### Claude 3 from Anthropic
 
-- Unlimited budget: `claude-3-opus-20240229`
+- Unlimited budget: `claude-3-5-sonnet-20240620`
 - Limited budget: `claude-3-sonnet-20240229`
 
 #### GPT-4o from OpenAI