[ie/ard] Revert to using old id

[Grub4K]

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Using the new id is inconvenient for users bc it is just too long. Since the old id might be removed eventually though, this PR provides a fallback to the new id if it ever breaks, with a warning to open an issue about the breakage

People should use --print-to-file "%(_old_archive_ids)#l" archive.txt to put the new id into their archives, so when the old id disappears the connection is not completely lost

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[dirkf]

If the old ID really is unreliable, how about using a digest of the new ID?

[Grub4K]

Thats a fair comment, and will limit the id to a fixed length, however that means we cant get the id back from the hashed id easily. One benefit of the new ID is that we can get back to the media using that ID. Keeping the full id under display_id is def something we want to do either way though so that could cover that. Wed have to think about it @seproDev

[seproDev]

We reached out to ARD and asked if the contentId field will be removed. Here is their response:

Das genannte Feld wird mittelfristig noch weiterhin ausgegeben, wird aber längerfristig ausgebaut werden. Wann genau das sein wird, können wir leider noch nicht sagen.

This field will continue to be returned in the medium term, but will be removed in the longer term. Unfortunately, we cannot yet say exactly when this will be.

To reiterate what Grub4K said: If you are using the download archive, you should add --print-to-file "%(_old_archive_ids)#l" archive.txt to put the new ID into your archive. Otherwise, the connection between the old and new IDs will be completely lost once the old IDs are removed.