feat: Added blurhash to image metadata

[skalidindi53]

☑️ Resolves

• Fix Add blurhash to image metadata #12351

🛠️ API Checklist

🚧 Tasks

• Added blurhash to image metadata

🏁 Checklist

• ⛑️ Tests (unit and/or integration) are included or not possible
• 📘 API documentation in docs/ has been updated or is not required
• 🔖 Capability is added or not needed

[nickvergessen]

@SystemKeeper can/want to give this a try?

[nickvergessen]

/backport to stable30

[SystemKeeper]

@SystemKeeper can/want to give this a try?

The PR works fine for me and correctly returns the blurhash.

Would it make sense to rename size-related methods/variables like getMetadataPhotosSizeForFileId to getImageMetadataForFileId or the like to make it clearer that this is not only about size?

One thing I noticed is that blurhash generation has since been moved to a background job: https://github.com/nextcloud/server/blob/560282a47bf3f9dca4653f89d530a6e1dd144f5f/lib/private/Blurhash/Listener/GenerateBlurhashMetadata.php#L57-L61

So when we upload images, a blurhash will only be available after the next background run, which might limit the usefulness a bit...

Example from ios:

[nickvergessen]

One thing I noticed is that blurhash generation has since been moved to a background job

Hmpf, makes sense performancewise, but yeah kind of kills the feature