feat: adding a sample app showcasing the usage of the cloudinary flutter sdk

[heysagnik]

This pull request added a sample app that showcases the usage of the cloudinary flutter sdk.

Memories App

A beautiful photo memories app built with Flutter, showcasing Cloudinary SDK integration for cloud-based image storage and management.

Features

• 📸 Select multiple photos from gallery
• ☁️ Cloud storage with Cloudinary
• 🖼️ Optimized image delivery and transformations
• 📝 Create named memory collections
• 💾 Persistent data storage
• 📅 Automatic date tracking for each memory
• 🗑️ Delete memories and cloud images
• 🌐 Seamless image upload and retrieval
• 🔒 Secure image storage with environment variables

Home screen	Add memory	Photo viewer

[heysagnik]

this solves #30

hi @adimiz1
@kalifyaniv-cloudinary , looking ahead for your opinion on this.

This is a Part of Hacktoberfest 2025