The OpenCV.js library includes QR code detection functionality (cv.QRCodeDetector and cv.QRCodeDetectorAruco), but these classes were missing from the TypeScript definitions, preventing developers from using them with proper type checking and IntelliSense support.

This PR adds comprehensive TypeScript definitions for:

• QRCodeDetector - Standard QR code detection and decoding
• QRCodeDetectorAruco - Aruco-based QR code detection for improved robustness
• QRCodeDetectorAruco_Params - Configuration parameters for Aruco detection

Key Features Added

All standard QR code detection methods are now properly typed:

• detect() - Detect QR codes and return corner points
• decode() - Decode a previously detected QR code
• detectAndDecode() - Detect and decode in one step
• detectMulti() / decodeMulti() / detectAndDecodeMulti() - Handle multiple QR codes
• Proper memory management with delete() method

Comprehensive Testing

The implementation includes both API verification tests and functional tests with real QR code images:

• API Tests: Verify all classes and methods are properly exposed
• Functional Tests: Use an actual QR code image to test detection and decoding functionality
• Integration Tests: Demonstrate proper image loading, format conversion, and memory management

// Example of functional test
const detector = new cv.QRCodeDetector();
const jimpSrc = await Jimp.read("test-qr.png");
const img = cv.matFromImageData(jimpSrc.bitmap);
const imgBGR = new cv.Mat();
cv.cvtColor(img, imgBGR, cv.COLOR_RGBA2BGR);

const points = new cv.Mat();
const decodedText = detector.detectAndDecode(imgBGR, points);
expect(decodedText).toBe("Hello OpenCV.js QR Test!");

Usage Example

import cvReadyPromise from "@techstark/opencv-js";

async function detectQRCode() {
  const cv = await cvReadyPromise;
  
  // TypeScript now provides full IntelliSense support
  const detector = new cv.QRCodeDetector();
  const points = new cv.Mat();
  
  // All methods have proper type checking
  const decoded: string = detector.detectAndDecode(image, points);
  
  // For multiple QR codes
  const arucoDetector = new cv.QRCodeDetectorAruco();
  const decodedInfo: string[] = [];
  const found: boolean = arucoDetector.detectAndDecodeMulti(image, decodedInfo);
  
  detector.delete();
  arucoDetector.delete();
}

The implementation follows existing patterns in the codebase and includes 23 comprehensive tests that verify both API availability and actual QR code detection functionality. All tests pass, confirming that existing functionality remains unaffected.

Fixes #35.

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