Disable live agent text streaming by default and enable thoughts panel by default

Disable live agent text streaming by default and enable thoughts panel by default

Summary

Turned off live text streaming rendering in the TUI by default to reduce visual jitter.

Added settings.stream_agent_text (default false) and wired request creation to pass the streaming callback only when that setting is enabled.

Changed session defaults so the thoughts panel starts enabled (SessionState.show_thoughts = True) to keep reasoning visible even with text streaming disabled.

Kept tinyagent event streaming in place for tool lifecycle handling and final message assembly.

Key behavioral detail

RequestOrchestrator._handle_message_update() now appends text_delta content to _debug_raw_stream_accum even when no streaming callback is attached. This preserves interrupted-response recovery behavior when live streaming output is disabled.

Files changed

• src/tunacode/ui/app.py
• src/tunacode/configuration/defaults.py
• src/tunacode/core/agents/main.py
• src/tunacode/core/session/state.py
• tests/unit/core/test_thinking_stream_routing.py
• tests/unit/core/test_session_state_defaults.py (new)
• tests/unit/configuration/test_default_config_stream_agent_text.py (new)
• tests/unit/ui/test_stream_agent_text_setting.py (new)

Validation

• uv run ruff check --fix src/tunacode/ui/app.py src/tunacode/core/agents/main.py src/tunacode/core/session/state.py src/tunacode/configuration/defaults.py tests/unit/core/test_thinking_stream_routing.py tests/unit/core/test_session_state_defaults.py tests/unit/configuration/test_default_config_stream_agent_text.py tests/unit/ui/test_stream_agent_text_setting.py ✅
• uv run pytest tests/unit/core/test_thinking_stream_routing.py tests/unit/core/test_session_state_defaults.py tests/unit/configuration/test_default_config_stream_agent_text.py tests/unit/ui/test_stream_agent_text_setting.py -q ✅
• uv run ruff check . ✅