Add Leave Management App prompt for Power Apps

[summitbaj]

Summary

This PR adds a new prompt template for creating a Leave Management App using Power Apps Copilot.

What's Added

• Leave Management App prompt - A comprehensive prompt for building an internal leave management system
• README.md - Complete documentation with prompt details, usage instructions, and author information
• Assets - Screenshot and sample JSON data for the leave management app

Features Covered

The prompt enables creation of a Power Apps solution with:

• ✅ Employee leave request submission (type, dates, reason)
• ✅ Manager approval/rejection workflow
• ✅ Leave history tracking
• ✅ Role-based access control (Employees vs Managers)
• ✅ Modern responsive UI with company branding

Usage

1. Copy the provided prompt
2. Paste into Power Apps Copilot
3. Generate and customize the app as needed

Files Changed

• prompts/power-apps/leave-management-app/README.md - Main prompt documentation
• prompts/power-apps/leave-management-app/assets/leave-management-app.png - App screenshot
• prompts/power-apps/leave-management-app/assets/sample.json - Sample data structure

This follows the established pattern of other Power Apps prompts in the repository and provides a complete solution for employee leave management scenarios.