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/lodash/delay.js

@@ -0,0 +1,28 @@
+var baseDelay = require('./_baseDelay'),
+    baseRest = require('./_baseRest'),
+    toNumber = require('./toNumber');
+
+/**
+ * Invokes `func` after `wait` milliseconds. Any additional arguments are
+ * provided to `func` when it's invoked.
+ *
+ * @static
+ * @memberOf _
+ * @since 0.1.0
+ * @category Function
+ * @param {Function} func The function to delay.
+ * @param {number} wait The number of milliseconds to delay invocation.
+ * @param {...*} [args] The arguments to invoke `func` with.
+ * @returns {number} Returns the timer id.
+ * @example
+ *
+ * _.delay(function(text) {
+ *   console.log(text);
+ * }, 1000, 'later');
+ * // => Logs 'later' after one second.
+ */
+var delay = baseRest(function(func, wait, args) {
+  return baseDelay(func, toNumber(wait) || 0, args);
+});
+
+module.exports = delay;