RFC Direct downloads and uploads from S3 compatible storage and CDNs (chunking v3)

Direct transfers and chunked upload "v3" for S3-compatible primary storage Problem With S3-compatible primary storage every byte a user downloads or uploads passes through PHP twice: object store → PHP → client and client → PHP → object store. A PHP-FPM worker is busy for the whole transfer, so the number of concurrent transfers is bounded by pm.max_children, and the server's bandwidth is spent twice. Video seeking issues a new range request through PHP for every seek. use_presigned_url (since 26) exists, but it only fills oc:downloadURL for clients that ask for it, does not set a file name (downloads are saved as urn:oid:<id>), breaks with SSE-C, and does not check storage wrappers (findings/F-09, security/S-02). Goals • Browsers download, stream and upload directly from/to the bucket or a CDN in front of it. • Nothing changes for WebDAV clients, sync clients and scripts. • No new upload protocol: chunked upload v2 stays the protocol, so a …