Add core components for task management and navigation

This commit introduces the foundational UI components and logic for the task management application, including task creation, calendar views, Kanban boards, and navigation elements.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: ceced2fc-aa46-458d-ba87-ddd4b7bb1518
Replit-Commit-Checkpoint-Type: full_checkpoint
Replit-Commit-Screenshot-Url: https://storage.googleapis.com/screenshot-production-us-central1/659922a9-0087-461c-90dd-6d9a58b81d4d/ceced2fc-aa46-458d-ba87-ddd4b7bb1518/yy9YLEW

client/src/lib/queryClient.ts

@@ -0,0 +1,57 @@
+import { QueryClient, QueryFunction } from "@tanstack/react-query";
+
+async function throwIfResNotOk(res: Response) {
+  if (!res.ok) {
+    const text = (await res.text()) || res.statusText;
+    throw new Error(`${res.status}: ${text}`);
+  }
+}
+
+export async function apiRequest(
+  method: string,
+  url: string,
+  data?: unknown | undefined,
+): Promise<Response> {
+  const res = await fetch(url, {
+    method,
+    headers: data ? { "Content-Type": "application/json" } : {},
+    body: data ? JSON.stringify(data) : undefined,
+    credentials: "include",
+  });
+
+  await throwIfResNotOk(res);
+  return res;
+}
+
+type UnauthorizedBehavior = "returnNull" | "throw";
+export const getQueryFn: <T>(options: {
+  on401: UnauthorizedBehavior;
+}) => QueryFunction<T> =
+  ({ on401: unauthorizedBehavior }) =>
+  async ({ queryKey }) => {
+    const res = await fetch(queryKey.join("/") as string, {
+      credentials: "include",
+    });
+
+    if (unauthorizedBehavior === "returnNull" && res.status === 401) {
+      return null;
+    }
+
+    await throwIfResNotOk(res);
+    return await res.json();
+  };
+
+export const queryClient = new QueryClient({
+  defaultOptions: {
+    queries: {
+      queryFn: getQueryFn({ on401: "throw" }),
+      refetchInterval: false,
+      refetchOnWindowFocus: false,
+      staleTime: Infinity,
+      retry: false,
+    },
+    mutations: {
+      retry: false,
+    },
+  },
+});

client/src/lib/utils.ts

@@ -0,0 +1,6 @@
+import { clsx, type ClassValue } from "clsx"
+import { twMerge } from "tailwind-merge"
+
+export function cn(...inputs: ClassValue[]) {
+  return twMerge(clsx(inputs))
+}