feat(image-compression): add sharp-based compression for AI providers

[titan-juspay]

🎯 Overview

Implements automatic image compression for AI providers with provider-specific size limits to optimize API requests and reduce costs.

📝 Changes

New Files

• src/utils/imageCompressor.ts - Core image compression utility with Sharp
• src/types/imageCompressor.ts - TypeScript type definitions
• test/imageCompressor.test.ts - Comprehensive test suite

Features

✅ Provider-specific size limits (OpenAI: 20MB, Anthropic: 5MB, Google: 4MB)
✅ Automatic quality reduction (starts at 90%, reduces by 10% per attempt)
✅ Format conversion support (JPEG, PNG, WebP)
✅ Maintains aspect ratio during compression
✅ Detailed compression statistics
✅ Error handling and validation

Dependencies

• Added sharp (^0.33.2) for high-performance image processing
• Added @types/sharp (^0.32.0) for TypeScript support

🧪 Testing

All tests passing with comprehensive coverage:

• Compression within size limits
• Format conversion
• Quality reduction
• Error handling
• Edge cases

📚 Related

Closes #553

👤 Author

Implementation by: Charan V (charan.v@juspay.in)

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Co-authored-by: Charan V charan.v@juspay.in