electrs feature request: "First seen" timestamp on transactions

I would like to be able to display to the user what time a transaction was first seen in the mempool but also after the transaction has been confirmed be able to show "Confirmed after X minutes".

Even if the first seen timestamp can't be persistent, it would be great to at least attach it to mempool transactions.

Currently solving this at mempool.space with a custom solution but would be nice having it built into electrs.