- Add isImageLine() to terminal-image.ts with single startsWith check based on detected terminal protocol
- Replace dual includes() checks in tui.ts with imported isImageLine()
- Add image line handling to markdown.ts to skip wrapping and margins for image escapes
- Consolidate Box cache into RenderCache type with childLines/width/bgSample/lines fields
- Use in-place mutation in applyLineResets() to avoid array allocation
- Custom tools: TypeScript modules that extend pi with new tools
- Custom TUI rendering via renderCall/renderResult
- User interaction via pi.ui (select, confirm, input, notify)
- Session lifecycle via onSession callback for state reconstruction
- Examples: todo.ts, question.ts, hello.ts
- Hook examples: permission-gate, git-checkpoint, protected-paths
- Session lifecycle centralized in AgentSession
- Works across all modes (interactive, print, RPC)
- Unified session event for hooks (replaces session_start/session_switch)
- Box component added to pi-tui
- Examples bundled in npm and binary releases
Fixes#190
