Add real-time streaming support for agent responses using Server-Sent
Events (SSE). Responses now appear as they're generated instead of
waiting for completion.
- Add run_stream method to BaseAgent and ExploreAgentImpl
- Add /agents/stream SSE endpoint to API router
- Add run_agent_stream method to CLI client
- Add --stream flag to chat and explore commands (enabled by default)
- Use --no-stream for batch mode with spinner
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>