Add WebP support to ext/exif#22213
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WebP stores EXIF metadata in a RIFF "EXIF" chunk whose payload is a raw TIFF block, the same data JPEG carries after its APP1 marker. Walk the RIFF chunks, locate the EXIF chunk, and hand its payload to the existing exif_process_TIFF_in_JPEG() parser, so no third-party library is needed. The chunk is accepted regardless of the VP8X extended-format flag, and an optional leading "Exif\0\0" marker is skipped when an encoder emits one. Closes phpGH-19904
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WebP keeps EXIF metadata in a RIFF
EXIFchunk whose payload is a raw TIFF block, the same bytes a JPEG carries after itsAPP1/Exif\0\0marker, soexif_read_data()can read it by handing the chunk to the existingexif_process_TIFF_in_JPEG()parser, with no new dependency. Chunk scanning is bounded by the declared RIFF size, theEXIFchunk is accepted whether or not the VP8X extended-format flag is set, and an optional leadingExif\0\0marker is tolerated. The phpinfo supported-filetypes line now lists what exif actually parses (it was missing HEIF too).Fixes #19904