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/tailwindcss/lib/util/escapeClassName.js

@@ -0,0 +1,24 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+Object.defineProperty(exports, "default", {
+    enumerable: true,
+    get: function() {
+        return escapeClassName;
+    }
+});
+const _postcssselectorparser = /*#__PURE__*/ _interop_require_default(require("postcss-selector-parser"));
+const _escapeCommas = /*#__PURE__*/ _interop_require_default(require("./escapeCommas"));
+function _interop_require_default(obj) {
+    return obj && obj.__esModule ? obj : {
+        default: obj
+    };
+}
+function escapeClassName(className) {
+    var _node_raws;
+    let node = _postcssselectorparser.default.className();
+    node.value = className;
+    var _node_raws_value;
+    return (0, _escapeCommas.default)((_node_raws_value = node === null || node === void 0 ? void 0 : (_node_raws = node.raws) === null || _node_raws === void 0 ? void 0 : _node_raws.value) !== null && _node_raws_value !== void 0 ? _node_raws_value : node.value);
+}