Updated handle regex to support the formatting used by bridgyfeds bluesky <=> mastodon bridge

https://github.com/snarfed/bridgy-fed/issues/381#issuecomment-1735683326

Big milestone, shipped Bluesky => fediverse user discovery! Search for @[handle]@atproto.brid.gy (eg @jay.bsky.team@atproto.brid.gy) in any fediverse server.

I noticed that with the current regex check, using a handle like the one in the above example would result in an Invalid name. error, even though it is a valid Mastodon profile. I made an adjustment to allow periods in the username component of the handle address.

mentioned in commit 4afe7d43

merged

Deployed! Thank you!

mentioned in merge request !70 (merged)