Added calls to saveState() after scaling, rotating, and removing layers to ensure changes are properly recorded in the undo/redo history. Also refactored the matting button UI for better layout and ensured saveState is called after matting results are applied.
Replaced localStorage usage in Canvas.js with asynchronous IndexedDB operations for saving, loading, and removing canvas state. Added a new db.js module to handle IndexedDB interactions, improving scalability and reliability of state persistence.
Introduces methods to save and load canvas state to localStorage, enabling persistence across sessions. Refactors image loading for drag-and-drop, file input, and clipboard paste to use FileReader and data:URL, improving compatibility and reliability. Updates layer addition to consistently update selection and save state. Calls loadInitialState on widget creation to restore previous state if available.
Implemented undo and redo history stacks in Canvas.js, including keyboard shortcuts (Ctrl+Z, Ctrl+Y/Shift+Z), and state saving on relevant actions. Added Undo and Redo buttons to the UI in Canvas_view.js, with dynamic enable/disable based on history state.
