fix: agent67 config — use Claude Sonnet as default model

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

agentexample/agent67/agent-config.yml

@@ -16,8 +16,8 @@ description: >
 type: react
 
 model:
-  provider: ollama
-  name: qwen2.5-coder:32b
+  provider: anthropic
+  name: claude-sonnet-4-20250514
   temperature: 0.3
   maxTokens: 4096
   fallback: