PromptRunner class

A centralized runner for interactive terminal prompts.

Composes TerminalSession + RenderOutput + key handling to provide a complete solution for interactive prompts.

Key feature: Never clears the entire terminal. Only clears lines written by the prompt/view itself, preserving any existing terminal content.

Usage:

final runner = PromptRunner();
final result = runner.run(
  render: (out) {
    out.writeln('My prompt content');
    out.writeln('More content');
  },
  onKey: (event) {
    if (event.type == KeyEventType.enter) return PromptResult.confirmed;
    if (event.type == KeyEventType.esc) return PromptResult.cancelled;
    return null; // continue loop
  },
);