Implement Undo/Redo for Canvas Operations

Problem Implement undo/redo for a canvas editor after a series of operations (move, resize, delete, group), where grouped operations undo and redo as a single unit.

Requirements

• Apply operations; undo() reverts the last operation, redo() reapplies it.
• History is bounded; grouped ops undo/redo together.

Areas to design

• Representing an operation so it can be inverted (or the prior state restored).
• The undo and redo stacks, and how a fresh operation clears the redo stack.
• Bounding history and coalescing grouped operations.

Example

• ops → undo() restores the previous state; redo() reapplies the undone op.