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/lib/syntax/node/Function.js

@@ -0,0 +1,41 @@
+import {
+    Function as FunctionToken,
+    RightParenthesis
+} from '../../tokenizer/index.js';
+
+
+export const name = 'Function';
+export const walkContext = 'function';
+export const structure = {
+    name: String,
+    children: [[]]
+};
+
+// <function-token> <sequence> )
+export function parse(readSequence, recognizer) {
+    const start = this.tokenStart;
+    const name = this.consumeFunctionName();
+    const nameLowerCase = name.toLowerCase();
+    let children;
+
+    children = recognizer.hasOwnProperty(nameLowerCase)
+        ? recognizer[nameLowerCase].call(this, recognizer)
+        : readSequence.call(this, recognizer);
+
+    if (!this.eof) {
+        this.eat(RightParenthesis);
+    }
+
+    return {
+        type: 'Function',
+        loc: this.getLocation(start, this.tokenStart),
+        name,
+        children
+    };
+}
+
+export function generate(node) {
+    this.token(FunctionToken, node.name + '(');
+    this.children(node);
+    this.token(RightParenthesis, ')');
+}