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/parser/sequence.cjs

@@ -0,0 +1,47 @@
+'use strict';
+
+const types = require('../tokenizer/types.cjs');
+
+function readSequence(recognizer) {
+    const children = this.createList();
+    let space = false;
+    const context = {
+        recognizer
+    };
+
+    while (!this.eof) {
+        switch (this.tokenType) {
+            case types.Comment:
+                this.next();
+                continue;
+
+            case types.WhiteSpace:
+                space = true;
+                this.next();
+                continue;
+        }
+
+        let child = recognizer.getNode.call(this, context);
+
+        if (child === undefined) {
+            break;
+        }
+
+        if (space) {
+            if (recognizer.onWhiteSpace) {
+                recognizer.onWhiteSpace.call(this, child, children, context);
+            }
+            space = false;
+        }
+
+        children.push(child);
+    }
+
+    if (space && recognizer.onWhiteSpace) {
+        recognizer.onWhiteSpace.call(this, null, children, context);
+    }
+
+    return children;
+}
+
+exports.readSequence = readSequence;