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/css-tree/cjs/syntax/node/GeneralEnclosed.cjs

@@ -0,0 +1,51 @@
+'use strict';
+
+const types = require('../../tokenizer/types.cjs');
+
+const name = 'GeneralEnclosed';
+const structure = {
+    function: [String, null],
+    children: [[]]
+};
+
+// <function-token> <any-value> )
+// ( <any-value> )
+function parse() {
+    const start = this.tokenStart;
+    let functionName = null;
+
+    if (this.tokenType === types.Function) {
+        functionName = this.consumeFunctionName();
+    } else {
+        this.eat(types.LeftParenthesis);
+    }
+
+    const children = this.readSequence(this.scope.Value);
+
+    if (!this.eof) {
+        this.eat(types.RightParenthesis);
+    }
+
+    return {
+        type: 'GeneralEnclosed',
+        loc: this.getLocation(start, this.tokenStart),
+        function: functionName,
+        children
+    };
+}
+
+function generate(node) {
+    if (node.function) {
+        this.token(types.Function, node.function + '(');
+    } else {
+        this.token(types.LeftParenthesis, '(');
+    }
+
+    this.children(node);
+    this.token(types.RightParenthesis, ')');
+}
+
+exports.generate = generate;
+exports.name = name;
+exports.parse = parse;
+exports.structure = structure;