Enable Drag and Drop on Adding Plugin Upload

A WordPress plugin that adds drag and drop capabilities to the plugin upload form on /wp-admin/plugin-install.php.

Features:

• Drag and drop ZIP files directly onto the upload form
• Visual feedback during drag operations
• Click-to-browse functionality on the drop zone
• Automatic file validation (ZIP files only)
• Success/error messages for user feedback
• Smooth animations and transitions

How It Works:

The plug-in: * Only loads on the plug-in install page (plugin-install.php) * Adds a visual drop zone below the upload form * Handles drag and drop events * Validates dropped files (must be ZIP files) * Automatically populates the file input when a file is dropped * Provides visual feedback during drag operations

Browser Support:

Works in all modern browsers that support the HTML5 Drag and Drop API: * Chrome * Firefox * Safari * Edge