[Peek] Expand image format support for Image Previewer

[daverayment]

Summary of the Pull Request

This removes the hardcoded list of file extensions from Peek's Image Previewer code, and instead relies upon the list returned from BitmapDecoder directly, which represents the formats the end user's system is capable of decoding.

PR Checklist

• Closes: #AVIF image preview support File Explorer add ons #21958
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated
• New binaries: Added on the required places
  • JSON for signing for new binaries
  • WXS for installer for new binaries and localization folder
  • YML for CI pipeline for new test projects
  • YML for signed pipeline
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

The use of GetDecoderInformationEnumerator() to get all WIC-supported formats:

• Automatically picks up new codec support if installed on a user's system
• Is more accurate, directly reflecting what the system can handle
• Future-proofs the code against new image formats, i.e. we don't have to add to the list of supported extensions if Windows adds more (like HEIC etc.)

Validation Steps Performed

This was tested manually with a test folder of images in a variety of different formats, from popular filetypes like JPEG and GIF, to AVIF, cursor files, JPEGXL, and several example RAW files. I also tested with other non-image files, such as PDF, text file, MP3 and videos, to ensure the other previewers were unaffected.

Note: I don't have an example file for every supported image format.

Additions and Removals

On my Windows 11 machine, this PR adds Peek support for the following types:

.rle
.icon
.cur
.exif
.dng
.dds
.avci
.heics
.heifs
.avcs
.avifs
.PTX
.PXN
.DNG
.JXL

These were previously in the hardcoded list, but are not marked as compatible on my machine:

.jfi
.jif
.thumb
.r3d
.rwz

These may have been present on the original developer's machine when the list was curated. They should be picked up with this new code if a WIC decoder exists on the target machine for them.

Examples

Cursor:

JPEGXL (after adding system support via JXL WinThumb):

(Example JPEGXL images can be created by converting existing image files with https://squoosh.app/)

DNG (drone footage still):

Important Note

HEIC and JPEGXL are marked in Windows as compatible, but require separate installation. For HEIC this means paying a licence, as it is patent-encumbered. For JPEGXL, Windows support is not yet built-in, but can be added via a third party extension. If the user does not have a WIC-compatible codec installed, there will be no change from the previous version of Peek, i.e. the UnsupportedFilePreviewer will be used to show overview information of the file:

[crutkas]

This is real fire