Add addListeners / removeListeners with configurable keyboard shortcuts

[math-krish]

Closes #2

I just want to say, I love your implementation! I'm not entirely sure if this works in replicache, but I tested it with a plain react application. Please let me know if there's anything you'd like me to change

What’s Changed

Adds optional keyboard shortcut support to UndoManager via two new methods:

undoManager.addListeners(window)
undoManager.removeListeners(window)

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New Constructor Options

Option	Type	Default	Description
enableShortcuts	boolean	false	Opt-in to keyboard shortcut handling
shortcuts	ShortcutOptions	see below	Per-platform key binding overrides

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Key Binding Type

KeyBinding is typed as a subset of the browser’s native KeyboardEventInit:

• key

• shiftKey

• altKey

• ctrlKey

• metaKey

No extra dependencies — fully standard.

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Platform Detection

Uses event.metaKey and event.ctrlKey directly from the event.

No deprecated navigator.platform.

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Example

const undoManager = new UndoManager({
  enableShortcuts: true,
  shortcuts: {
    other: {
      undo: { key: 'z' },
      redo: [{ key: 'y' }, { key: 'z', shiftKey: true }],
    },
    mac: {
      undo: { key: 'z' },
      redo: [{ key: 'z', shiftKey: true }],
    },
  },
})

undoManager.addListeners(window)

// later...
undoManager.removeListeners(window)

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Testing

• 11 new unit tests covering:

  • Default shortcuts

  • Custom bindings

  • enableShortcuts: false

  • metaKey vs ctrlKey paths

  • removeListeners cleanup

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