resolve #61488

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• Resolves: [Bug]: Chunked upload to object-store (S3) primary fails with 413 "Insufficient space" for any user with a finite quota, regardless of free space #61488

Summary

On primary object storage (S3 and other object stores) with a finite per-user
quota, chunked uploads fail with HTTP 413 EntityTooLarge / "Insufficient
space" regardless of how much quota is actually free. A ~250 MB upload was
rejected with ~8.4 GiB of free quota; reducing the chunk size had no effect,
and setting the quota to Unlimited worked around it.

Root cause is in OC\Files\Storage\Wrapper\Quota::writeStream(). Chunk parts
are written to the quota-exempt uploads/ path, for which free_space()
returns the wrapped storage's value. Object stores return
FileInfo::SPACE_UNLIMITED (-3) there, so the if ($size < $free) check
evaluates $size < -3, which is always false, and the method throws
NotEnoughSpaceException.

writeStream() was the only write method missing the $free < 0 short-circuit
that file_put_contents(), copy(), copyFromStorage(), and
moveFromStorage() already use, and that QuotaPlugin::checkQuota() applies at
the DAV layer. The fix adds that guard. On local storage the bug does not
trigger because free_space() returns a real positive value for the uploads
path.

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

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@provokateurin

[0x7d8]

I assume backport would apply to this, for what versions?