Opt-in (-e bigFileMB=<size>): streams a multi-GB file from the device through
the app's chunked-upload path to the external nextcloud.khodak.me and verifies
the full size lands. Verified live: 1.5 GB and 5 GB both succeed end-to-end.
Big-file testing found single-PUT uploads 413 above the server's per-request
cap (Apache LimitRequestBody / PHP post_max_size / proxy limits). NextcloudProvider
now uploads files >chunkSize (100MB) via the dav/uploads chunked API: MKCOL a
session, PUT N chunks, then MOVE .file onto the destination (atomic assemble).
Bypasses any per-request cap so multi-GB files back up. Verified byte-exact
(multi-chunk) against live Nextcloud. SFTP already streams; single-PUT path
unchanged for <=100MB.
Instrumented test driving the real NextcloudProvider over TLS: connect,
create dir, atomic upload (temp+MOVE), list+size, download+content, then the
backup guarantee — Upload-only + KEEP yields SKIP and the cloud copy is
verified still present; MIRROR yields DELETE_REMOTE and the real delete is
confirmed. Creds passed via instrumentation args (ncUrl/ncUser/ncPass), never
committed. Verified passing on a Galaxy S23 (Android 16) against live Nextcloud.
amir