Yes I did address that part but honestly I can use the time of when it was sent into blockchain / transaction id which is generally really short as I said in the comment. I will hack a prototype tomorrow.

It is the long URL that also needs to be stored, not just the short URL.

If you want to use blockchain for this, I advise properly using a dedicated new blockchain, not spamming the Nano network.

Yes I agree about using a dedicated new blockchain but as I noted, that's as good as a sqlite torrent and so I mean, maybe people interested can use this but if it means having nodes out of complete charity (sorta as nano) then I do think that it might fall short.

The funny part is that I was thinking about creating a dedicated new blockchain but I felt "spamming" (honestly fair critique) was easier and more practical and currently more decentralized.