Restore tool call rendering with lifecycle tracking

[evantahler]

Summary

• Iterates the full OpenAI agents stream to detect tool_called and tool_output events
• Tracks tool call lifecycle (running → completed) with arguments and execution time
• Displays tool calls as a formatted tree with 🛠️ root label and proper status indicators
• Tool calls persist in chat history rather than disappearing after streaming ends

How it works

When the agent invokes a tool, the stream emits tool_called with the tool name, arguments, and call ID. When the tool completes, tool_output emits with the same call ID. The logger tracks both events and the UI renders them as a tree:

🛠️ Tool calls:
  ├─ ⏳ search({"q":"hello"})
  └─ ✓ read_file({...}) (1.2s)

Running calls show ⏳ (yellow), completed calls show ✓ with duration (green).

🤖 Generated with Claude Code