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/autoprefixer/lib/hacks/pixelated.js

@@ -0,0 +1,34 @@
+let OldValue = require('../old-value')
+let Value = require('../value')
+
+class Pixelated extends Value {
+  /**
+   * Different name for WebKit and Firefox
+   */
+  old(prefix) {
+    if (prefix === '-webkit-') {
+      return new OldValue(this.name, '-webkit-optimize-contrast')
+    }
+    if (prefix === '-moz-') {
+      return new OldValue(this.name, '-moz-crisp-edges')
+    }
+    return super.old(prefix)
+  }
+
+  /**
+   * Use non-standard name for WebKit and Firefox
+   */
+  replace(string, prefix) {
+    if (prefix === '-webkit-') {
+      return string.replace(this.regexp(), '$1-webkit-optimize-contrast')
+    }
+    if (prefix === '-moz-') {
+      return string.replace(this.regexp(), '$1-moz-crisp-edges')
+    }
+    return super.replace(string, prefix)
+  }
+}
+
+Pixelated.names = ['pixelated']
+
+module.exports = Pixelated