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/dom-helpers/cjs/scrollTo.js

@@ -0,0 +1,51 @@
+"use strict";
+
+var _interopRequireDefault = require("@babel/runtime/helpers/interopRequireDefault");
+
+exports.__esModule = true;
+exports.default = scrollTo;
+
+var _animationFrame = require("./animationFrame");
+
+var _height = _interopRequireDefault(require("./height"));
+
+var _isWindow = _interopRequireDefault(require("./isWindow"));
+
+var _offset = _interopRequireDefault(require("./offset"));
+
+var _scrollParent = _interopRequireDefault(require("./scrollParent"));
+
+var _scrollTop = _interopRequireDefault(require("./scrollTop"));
+
+/* eslint-disable no-nested-ternary */
+function scrollTo(selected, scrollParent) {
+  var offset = (0, _offset.default)(selected);
+  var poff = {
+    top: 0,
+    left: 0
+  };
+  if (!selected) return undefined;
+  var list = scrollParent || (0, _scrollParent.default)(selected);
+  var isWin = (0, _isWindow.default)(list);
+  var listScrollTop = (0, _scrollTop.default)(list);
+  var listHeight = (0, _height.default)(list, true);
+  if (!isWin) poff = (0, _offset.default)(list);
+  offset = {
+    top: offset.top - poff.top,
+    left: offset.left - poff.left,
+    height: offset.height,
+    width: offset.width
+  };
+  var selectedHeight = offset.height;
+  var selectedTop = offset.top + (isWin ? 0 : listScrollTop);
+  var bottom = selectedTop + selectedHeight;
+  listScrollTop = listScrollTop > selectedTop ? selectedTop : bottom > listScrollTop + listHeight ? bottom - listHeight : listScrollTop;
+  var id = (0, _animationFrame.request)(function () {
+    return (0, _scrollTop.default)(list, listScrollTop);
+  });
+  return function () {
+    return (0, _animationFrame.cancel)(id);
+  };
+}
+
+module.exports = exports["default"];