Add AVIF Decode ability

[timvw74]

This PR completes AVIF support by adding the ability to load AVIF images, It uses the avifdec tool to load and extract data from the image file.

[Copilot]

Pull Request Overview

This PR adds AVIF image format decoding capabilities to complement existing encoding support by implementing the AVIFDecoder class that uses the external avifdec tool to decode AVIF files into standard image formats.

• Implements AVIF image decoding using the external avifdec tool
• Adds AVIF format detection and metadata parsing capabilities
• Provides comprehensive test coverage for the decoder functionality

Reviewed Changes

Copilot reviewed 8 out of 11 changed files in this pull request and generated 10 comments.

Show a summary per file

File	Description
test/AVIFDecoderTests.cs	Test suite covering AVIF file identification, decoding, and format detection
src/Native.cs	Adds reference to avifdec executable alongside existing avifenc
src/AVIFInfo.cs	Data model for storing parsed AVIF metadata information
src/AVIFImageFormatDetector.cs	Format detector for identifying AVIF files by header signature
src/AVIFFormat.cs	Updates format class to include decoder, encoder, and singleton instance
src/AVIFEncoder.cs	Updates to use renamed CAVIFENC constant
src/AVIFDecoder.cs	Core decoder implementation using external avifdec tool
src/AVIFConfigurationModule.cs	Configuration module registering decoder and format detector

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[Copilot]

Parameter name has a typo: 'vaildAVIF' should be 'validAVIF'.

[Copilot]

Remove extra blank lines to maintain consistent code formatting.

Suggested change

[Copilot]

The condition should be >= not <=. A header with length less than HeaderSize (12) cannot contain a valid AVIF signature that requires checking bytes at positions 4-11.

Suggested change

	bool isAVIF = header.Length <= HeaderSize && IsAvif(header);
	bool isAVIF = header.Length >= HeaderSize && IsAvif(header);

[Copilot]

Using int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully.

[Copilot]

Multiple uses of int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully for all integer parsing operations.

[Copilot]

Multiple uses of int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully for all integer parsing operations.

[Copilot]

Multiple uses of int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully for all integer parsing operations.

[Copilot]

Multiple uses of int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully for all integer parsing operations.

[Copilot]

Multiple uses of int.Parse without validation can throw exceptions on malformed input. Consider using int.TryParse and handle parsing failures gracefully for all integer parsing operations.

[Copilot]

File deletion operations can throw exceptions if files are in use or access is denied. Wrap these calls in try-catch blocks to prevent cleanup failures from propagating.

Suggested change

	File.Delete(inputFilePath);
	File.Delete(outputFilePath);
	try
	{
	File.Delete(inputFilePath);
	}
	catch
	{
	// Suppress any exceptions during cleanup
	}
	try
	{
	File.Delete(outputFilePath);
	}
	catch
	{
	// Suppress any exceptions during cleanup
	}

[Spacefish]

LGTM