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/confbox/dist/shared/confbox.9745c98f.d.ts

@@ -0,0 +1,24 @@
+interface FormatOptions {
+    /**
+     * A String or Number object that's used to insert white space into the output JSON string for readability purposes.
+     *
+     * When provided, identation won't be auto detected anymore.
+     */
+    indent?: string | number;
+    /**
+     * Set to `false` to skip indentation preservation.
+     */
+    preserveIndentation?: boolean;
+    /**
+     * Set to `false` to skip whitespace preservation.
+     */
+    preserveWhitespace?: boolean;
+    /**
+     * The number of characters to sample from the start of the text.
+     *
+     * Default: 1024
+     */
+    sampleSize?: number;
+}
+
+export type { FormatOptions as F };