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/@testing-library/dom/dist/queries/title.js

@@ -0,0 +1,37 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.queryByTitle = exports.queryAllByTitle = exports.getByTitle = exports.getAllByTitle = exports.findByTitle = exports.findAllByTitle = void 0;
+var _queryHelpers = require("../query-helpers");
+var _helpers = require("../helpers");
+var _allUtils = require("./all-utils");
+const isSvgTitle = node => {
+  var _node$parentElement;
+  return node.tagName.toLowerCase() === 'title' && ((_node$parentElement = node.parentElement) == null ? void 0 : _node$parentElement.tagName.toLowerCase()) === 'svg';
+};
+const queryAllByTitle = (container, text, {
+  exact = true,
+  collapseWhitespace,
+  trim,
+  normalizer
+} = {}) => {
+  (0, _helpers.checkContainerType)(container);
+  const matcher = exact ? _allUtils.matches : _allUtils.fuzzyMatches;
+  const matchNormalizer = (0, _allUtils.makeNormalizer)({
+    collapseWhitespace,
+    trim,
+    normalizer
+  });
+  return Array.from(container.querySelectorAll('[title], svg > title')).filter(node => matcher(node.getAttribute('title'), node, text, matchNormalizer) || isSvgTitle(node) && matcher((0, _allUtils.getNodeText)(node), node, text, matchNormalizer));
+};
+const getMultipleError = (c, title) => `Found multiple elements with the title: ${title}.`;
+const getMissingError = (c, title) => `Unable to find an element with the title: ${title}.`;
+const queryAllByTitleWithSuggestions = exports.queryAllByTitle = (0, _queryHelpers.wrapAllByQueryWithSuggestion)(queryAllByTitle, queryAllByTitle.name, 'queryAll');
+const [queryByTitle, getAllByTitle, getByTitle, findAllByTitle, findByTitle] = (0, _allUtils.buildQueries)(queryAllByTitle, getMultipleError, getMissingError);
+exports.findByTitle = findByTitle;
+exports.findAllByTitle = findAllByTitle;
+exports.getByTitle = getByTitle;
+exports.getAllByTitle = getAllByTitle;
+exports.queryByTitle = queryByTitle;