feat: add escape key to cancel branch selection screen

[ericanderson]

Summary

• Added escape key cancellation support to interactive branch selection screens
• Created promptWithCancel utility wrapper around inquirer prompts
• Updated both local and remote commands to handle escape key gracefully
• Pressing ESC during branch selection cancels the operation and returns to command prompt

Implementation Details

• New Utility: src/utils/promptWithCancel.ts - Wraps inquirer prompts with escape key handling
• Enhanced Commands: Both PruneLocalBranches and PrunePullRequests now support escape cancellation
• Terminal Safety: Proper cleanup of raw mode and event listeners
• Race Condition Protection: Prevents double-resolution of promises
• Non-TTY Support: Gracefully handles environments without TTY support

Test Coverage

• 7 comprehensive test cases covering all scenarios:
  • Normal prompt completion
  • Escape key cancellation
  • Non-TTY environments
  • Error propagation
  • Ctrl+C handling
  • Race condition prevention
  • Terminal state restoration

User Experience

Users can now press ESC during interactive branch selection to:

1. Cancel the current branch selection
2. Exit cleanly without making any changes
3. Return to the command prompt immediately

This follows common CLI UX patterns and provides users with a quick escape route if they accidentally start an operation or want to abort after seeing the branch list.

Documentation

Updated README.md with new "Interactive Mode" sections explaining the escape key functionality for all commands that support interactive selection.

Fixes #24

🤖 Generated with Claude Code

[ericanderson]

dont uses any. fix this to be proper types.