In user bio settings, remove Twitter as an option and replace with Bluesky

While it's already possible to leave the box for the Twitter link in bios unchecked, I feel this company has come to stand for the opposite of everything Heartbeat stands for. It feels very off-brand to me to see that listed as a social link option.

Bluesky's functionality and safety tools are much more in line with the inclusion, respect, and accessibility I know Heartbeat wants to help foster in online community.