Resume an interrupted YouTube Data API resumable upload session using Content-Range probing and budget quota for bulk uploads

Steps

1. Initiate the resumable session with a POST to videos.insert using uploadType=resumable, and capture the session's upload URL from the response's Location header
2. On interruption, send an empty PUT request to that same upload URL with a Content-Range header of bytes */TOTAL_SIZE to query how much of the file the server actually received
3. Read the resulting HTTP 308 (Resume Incomplete) response's Range header to determine the last byte offset successfully stored server-side
4. Send a subsequent PUT request containing only the remaining bytes of the file, with a Content-Range header offset to start exactly where the 308 response indicated
5. On full completion the server returns 201 Created along with the newly created video resource
6. Before running any bulk-upload job, look up the current per-call quota cost of videos.insert in the API's quota documentation, since it costs far more units than typical read calls and can exhaust the default daily project quota after only a handful of uploads