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/@tanstack/react-query/build/modern/useBaseQuery.js

@@ -0,0 +1,105 @@
+"use client";
+
+// src/useBaseQuery.ts
+import * as React from "react";
+import { environmentManager, noop, notifyManager } from "@tanstack/query-core";
+import { useQueryClient } from "./QueryClientProvider.js";
+import { useQueryErrorResetBoundary } from "./QueryErrorResetBoundary.js";
+import {
+  ensurePreventErrorBoundaryRetry,
+  getHasError,
+  useClearResetErrorBoundary
+} from "./errorBoundaryUtils.js";
+import { useIsRestoring } from "./IsRestoringProvider.js";
+import {
+  ensureSuspenseTimers,
+  fetchOptimistic,
+  shouldSuspend,
+  willFetch
+} from "./suspense.js";
+function useBaseQuery(options, Observer, queryClient) {
+  if (process.env.NODE_ENV !== "production") {
+    if (typeof options !== "object" || Array.isArray(options)) {
+      throw new Error(
+        'Bad argument type. Starting with v5, only the "Object" form is allowed when calling query related functions. Please use the error stack to find the culprit call. More info here: https://tanstack.com/query/latest/docs/react/guides/migrating-to-v5#supports-a-single-signature-one-object'
+      );
+    }
+  }
+  const isRestoring = useIsRestoring();
+  const errorResetBoundary = useQueryErrorResetBoundary();
+  const client = useQueryClient(queryClient);
+  const defaultedOptions = client.defaultQueryOptions(options);
+  client.getDefaultOptions().queries?._experimental_beforeQuery?.(
+    defaultedOptions
+  );
+  const query = client.getQueryCache().get(defaultedOptions.queryHash);
+  if (process.env.NODE_ENV !== "production") {
+    if (!defaultedOptions.queryFn) {
+      console.error(
+        `[${defaultedOptions.queryHash}]: No queryFn was passed as an option, and no default queryFn was found. The queryFn parameter is only optional when using a default queryFn. More info here: https://tanstack.com/query/latest/docs/framework/react/guides/default-query-function`
+      );
+    }
+  }
+  defaultedOptions._optimisticResults = isRestoring ? "isRestoring" : "optimistic";
+  ensureSuspenseTimers(defaultedOptions);
+  ensurePreventErrorBoundaryRetry(defaultedOptions, errorResetBoundary, query);
+  useClearResetErrorBoundary(errorResetBoundary);
+  const isNewCacheEntry = !client.getQueryCache().get(defaultedOptions.queryHash);
+  const [observer] = React.useState(
+    () => new Observer(
+      client,
+      defaultedOptions
+    )
+  );
+  const result = observer.getOptimisticResult(defaultedOptions);
+  const shouldSubscribe = !isRestoring && options.subscribed !== false;
+  React.useSyncExternalStore(
+    React.useCallback(
+      (onStoreChange) => {
+        const unsubscribe = shouldSubscribe ? observer.subscribe(notifyManager.batchCalls(onStoreChange)) : noop;
+        observer.updateResult();
+        return unsubscribe;
+      },
+      [observer, shouldSubscribe]
+    ),
+    () => observer.getCurrentResult(),
+    () => observer.getCurrentResult()
+  );
+  React.useEffect(() => {
+    observer.setOptions(defaultedOptions);
+  }, [defaultedOptions, observer]);
+  if (shouldSuspend(defaultedOptions, result)) {
+    throw fetchOptimistic(defaultedOptions, observer, errorResetBoundary);
+  }
+  if (getHasError({
+    result,
+    errorResetBoundary,
+    throwOnError: defaultedOptions.throwOnError,
+    query,
+    suspense: defaultedOptions.suspense
+  })) {
+    throw result.error;
+  }
+  ;
+  client.getDefaultOptions().queries?._experimental_afterQuery?.(
+    defaultedOptions,
+    result
+  );
+  if (defaultedOptions.experimental_prefetchInRender && !environmentManager.isServer() && willFetch(result, isRestoring)) {
+    const promise = isNewCacheEntry ? (
+      // Fetch immediately on render in order to ensure `.promise` is resolved even if the component is unmounted
+      fetchOptimistic(defaultedOptions, observer, errorResetBoundary)
+    ) : (
+      // subscribe to the "cache promise" so that we can finalize the currentThenable once data comes in
+      query?.promise
+    );
+    promise?.catch(noop).finally(() => {
+      observer.updateResult();
+    });
+  }
+  return !defaultedOptions.notifyOnChangeProps ? observer.trackResult(result) : result;
+}
+export {
+  useBaseQuery
+};
+//# sourceMappingURL=useBaseQuery.js.map