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/createPlugin.js

@@ -0,0 +1,32 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", {
+    value: true
+});
+Object.defineProperty(exports, "default", {
+    enumerable: true,
+    get: function() {
+        return _default;
+    }
+});
+function createPlugin(plugin, config) {
+    return {
+        handler: plugin,
+        config
+    };
+}
+createPlugin.withOptions = function(pluginFunction, configFunction = ()=>({})) {
+    const optionsFunction = function(options) {
+        return {
+            __options: options,
+            handler: pluginFunction(options),
+            config: configFunction(options)
+        };
+    };
+    optionsFunction.__isOptionsFunction = true;
+    // Expose plugin dependencies so that `object-hash` returns a different
+    // value if anything here changes, to ensure a rebuild is triggered.
+    optionsFunction.__pluginFunction = pluginFunction;
+    optionsFunction.__configFunction = configFunction;
+    return optionsFunction;
+};
+const _default = createPlugin;