[zfoong]

Summary

• embed a centered launch menu inside the Textual TUI with matching styling, start/settings/exit controls, and a provider/API key dialog
• transition from the menu directly into the chat layout without dropping to the shell and announce the selected provider
• allow main/agent startup to pass provider defaults into the TUI so credentials can be applied before chatting

Testing

• python -m compileall core/main.py core/agent_base.py core/tui_interface.py

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Codex Task