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/components/examples/BottomNavigation.tsx

@@ -0,0 +1,17 @@
+import BottomNavigation from '../BottomNavigation';
+
+export default function BottomNavigationExample() {
+  return (
+    <div className="relative h-[400px] bg-muted/20">
+      <div className="p-4">
+        <h3 className="text-lg font-semibold mb-2">App Content Area</h3>
+        <p className="text-muted-foreground">
+          This is where your main app content would be displayed. 
+          The bottom navigation is fixed at the bottom of the screen.
+        </p>
+      </div>
+      
+      <BottomNavigation />
+    </div>
+  );
+}