## Summary
- Adds a new `/statusline` command to configure TUI footer status line
- Introduces reusable `MultiSelectPicker` component with keyboard
navigation, optional ordering and toggle support
- Implement status line setup modal that persist configuration to
config.toml
## Status Line Items
The following items can be displayed in the status line:
- **Model**: Current model name (with optional reasoning level)
- **Context**: Remaining/used context window percentage
- **Rate Limits**: 5-day and weekly usage limits
- **Git**: Current branch (with optimized lookups)
- **Tokens**: Used tokens, input/output token counts
- **Session**: Session ID (full or shortened prefix)
- **Paths**: Current directory, project root
- **Version**: Codex version
## Features
- Live preview while configuring status line items
- Fuzzy search filtering in the picker
- Intelligent truncation when items don't fit
- Items gracefully omit when data is unavailable
- Configuration persists to `config.toml`
- Validates and warns about invalid status line items
## Test plan
- [x] Run `/statusline` and verify picker UI appears
- [x] Toggle items on/off and verify live preview updates
- [x] Confirm selection persists after restart
- [x] Verify truncation behavior with many items selected
- [x] Test git branch detection in and out of git repos
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Co-authored-by: Josh McKinney <joshka@openai.com>
