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/chai/sauce.browsers.js

@@ -0,0 +1,106 @@
+
+/*!
+ * Chrome
+ */
+
+exports['SL_Chrome'] = {
+    base: 'SauceLabs'
+  , browserName: 'chrome'
+};
+
+/*!
+ * Firefox
+ */
+
+ exports['SL_Firefox'] = {
+     base: 'SauceLabs'
+   , browserName: 'firefox'
+ };
+
+ exports['SL_Firefox_ESR'] = {
+     base: 'SauceLabs'
+   , browserName: 'firefox'
+   , version: 38
+ };
+
+/*!
+ * Internet Explorer
+ */
+
+exports['SL_IE'] = {
+    base: 'SauceLabs'
+  , browserName: 'internet explorer'
+};
+
+/*!
+ * TODO: fails because of Uint8Array support
+ *
+exports['SL_IE_Old'] = {
+    base: 'SauceLabs'
+  , browserName: 'internet explorer'
+  , version: 10
+};
+*/
+
+exports['SL_Edge'] = {
+    base: 'SauceLabs'
+  , browserName: 'microsoftedge'
+};
+
+/*!
+ * Safari
+ */
+
+exports['SL_Safari'] = {
+    base: 'SauceLabs'
+  , browserName: 'safari'
+  , platform: 'Mac 10.11'
+};
+
+/*!
+ * iPhone
+ */
+
+/*!
+ * TODO: These take forever to boot or shut down. Causes timeout.
+ *
+
+exports['SL_iPhone_6'] = {
+    base: 'SauceLabs'
+  , browserName: 'iphone'
+  , platform: 'Mac 10.8'
+  , version: '6'
+};
+
+exports['SL_iPhone_5-1'] = {
+    base: 'SauceLabs'
+  , browserName: 'iphone'
+  , platform: 'Mac 10.8'
+  , version: '5.1'
+};
+
+exports['SL_iPhone_5'] = {
+    base: 'SauceLabs'
+  , browserName: 'iphone'
+  , platform: 'Mac 10.6'
+  , version: '5'
+};
+
+*/
+
+/*!
+ * Android
+ */
+
+/*!
+ * TODO: fails because of error serialization
+ *
+
+exports['SL_Android_4'] = {
+    base: 'SauceLabs'
+  , browserName: 'android'
+  , platform: 'Linux'
+  , version: '4'
+};
+
+*/