feat(frontend): add API client, layout, and routing

- Create Axios-based API client with sources, jobs, and dashboard endpoints
- Add responsive Layout component with navigation sidebar
- Set up React Router with Dashboard, Backups, and Settings routes
- Configure TanStack Query provider with default options
- Use lucide-react for navigation icons

frontend/node_modules/fraction.js/examples/tape-measure.js

@@ -0,0 +1,16 @@
+/*
+Fraction.js v5.0.0 10/1/2024
+https://raw.org/article/rational-numbers-in-javascript/
+
+Copyright (c) 2024, Robert Eisele (https://raw.org/)
+Licensed under the MIT license.
+*/
+const Fraction = require('fraction.js');
+
+function closestTapeMeasure(frac) {
+
+    // A tape measure is usually divided in parts of 1/16
+
+    return Fraction(frac).roundTo("1/16");
+}
+console.log(closestTapeMeasure("1/3")); // 5/16