Whimsical

Build me a single-player flowchart tool like Whimsical. Requirements: - A local web app: Vite + React, shapes rendered as SVG. No backend, runs as a static build, fully offline. - Shapes: rectangle, rounded rectangle, diamond, ellipse, sticky note, text label. Drag to move, handles to resize, double-click to edit text inline. - Connectors attach to shape anchor points, stay attached when shapes move, route orthogonally with arrowheads, and can carry a text label. - Snap-to-grid plus alignment guides while dragging; keyboard support for copy/paste, delete, arrow-key nudge, and undo/redo via a history stack. - A toolbar with the shape palette and 8 preset fill colors. No free-form style panel. - Boards autosave to IndexedDB (via localforage), with JSON import/export; export the selection or the whole board as PNG and SVG. - No accounts, no telemetry, nothing leaves the browser. - Out of scope: real-time multiplayer, comments, wireframe component kits, and mind-map mode. Flowcharts and stickies only. - README: npm install / npm run dev, plus the keyboard shortcut list.