event carousel accentColor

[rrrliu]

accentColor is now configurable, rather than being only purple / orange

unfortunately this also means another ITicketData / IPODTicketData field, so we may need to remove another field with #2151

Screen.Recording.2024-12-09.at.4.57.47.PM.mov

[robknight]

This looks fine to me. I do notice that the accent color is not available for CSVTicketPipeline - do we think we'll need it for that?

Also flagging up for @artwyman that this will add another entry to POD tickets, which might affect Merkle tree depths in the long run.

[artwyman]

Thanks for the callout. Note that I closed #2151 figuring that now that we're out of the Devcon crisis mode we'd prefer other solutions. We can re-open it if we decide otherwise. I think the best answer is distribute artifacts which support a deeper Merkle tree, rather than forcing tickets to stay below 16 entries. There is a cost (adding 1 depth means 1 more Poseidon hash per entry in the circuit), but likely it's not big enough to be worth limiting our use cases too much. We should be watchful going forward for the point where we might cross further thresholds (32 would be next) if we haven't fleshed out the artifacts enough to cover all cases.

For this feature in particular, it seems a bit of a shame that this info has to go into every ticket rather than some sort of per-event metadata POD, but it would take a larger set of changes to distribute those.