Initial commit: Agile Project Manager

- Complete React + TypeScript application with Vite
- Dashboard with charts and metrics visualization
- Kanban board with drag-and-drop functionality
- Product backlog management with user stories
- Sprint planning and tracking features
- Comprehensive UI component library (shadcn/ui)
- Tailwind CSS styling with dark mode support
- Context-based state management
- Mock data for immediate testing and demonstration

components/ui/checkbox.tsx

@@ -0,0 +1,32 @@
+"use client";
+
+import * as React from "react";
+import * as CheckboxPrimitive from "@radix-ui/react-checkbox@1.1.4";
+import { CheckIcon } from "lucide-react";
+
+import { cn } from "./utils";
+
+function Checkbox({
+  className,
+  ...props
+}: React.ComponentProps<typeof CheckboxPrimitive.Root>) {
+  return (
+    <CheckboxPrimitive.Root
+      data-slot="checkbox"
+      className={cn(
+        "peer border bg-input-background dark:bg-input/30 data-[state=checked]:bg-primary data-[state=checked]:text-primary-foreground dark:data-[state=checked]:bg-primary data-[state=checked]:border-primary focus-visible:border-ring focus-visible:ring-ring/50 aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive size-4 shrink-0 rounded-[4px] border shadow-xs transition-shadow outline-none focus-visible:ring-[3px] disabled:cursor-not-allowed disabled:opacity-50",
+        className,
+      )}
+      {...props}
+    >
+      <CheckboxPrimitive.Indicator
+        data-slot="checkbox-indicator"
+        className="flex items-center justify-center text-current transition-none"
+      >
+        <CheckIcon className="size-3.5" />
+      </CheckboxPrimitive.Indicator>
+    </CheckboxPrimitive.Root>
+  );
+}
+
+export { Checkbox };