Update Subject EXIF metadata when transforming images.

[JimBobSquarePants]

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Description

Fixes #463

Adds automatic updating of SubjectLocation and SubjectArea EXIF metadata tags when transforming images.

[Copilot]

Pull Request Overview

This PR extends the metadata transformation pipeline to propagate EXIF subject location and area when images are transformed.

• ImageFrameMetadata now accepts a transformation matrix and calls SyncSubject to adjust EXIF tags.
• All format-specific metadata classes and interfaces have been updated to include a Matrix4x4 matrix parameter in AfterImageApply/AfterFrameApply.
• Added using System.Numerics; to enable Matrix4x4 references.

Reviewed Changes

Copilot reviewed 41 out of 41 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/ImageSharp/Metadata/ImageFrameMetadata.cs	Added matrix parameter to AfterFrameApply and call to SyncSubject
src/ImageSharp/Formats/Webp/WebpMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Webp/WebpFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Tiff/TiffMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Tiff/TiffFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Tga/TgaMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Qoi/QoiMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Png/PngMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Png/PngFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Pbm/PbmMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Jpeg/JpegMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Ico/IcoMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Ico/IcoFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/IFormatMetadata.cs	Added Matrix4x4 matrix parameter to AfterImageApply in interface
src/ImageSharp/Formats/IFormatFrameMetadata.cs	Added Matrix4x4 matrix parameter to AfterFrameApply in interface
src/ImageSharp/Formats/Gif/GifMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Gif/GifFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Cur/CurMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Cur/CurFrameMetadata.cs	Updated AfterFrameApply signature to include Matrix4x4 matrix
src/ImageSharp/Formats/Bmp/BmpMetadata.cs	Updated AfterImageApply signature to include Matrix4x4 matrix

Comments suppressed due to low confidence (1)

src/ImageSharp/Formats/IFormatFrameMetadata.cs:27

• [nitpick] The parameter name matrix is quite generic; consider renaming it to transformationMatrix for greater clarity in overrides.

public void AfterFrameApply<TPixel>(ImageFrame<TPixel> source, ImageFrame<TPixel> destination, Matrix4x4 matrix)