feat: user profiles

Allow users to set profile details and showcase them on a profile page. This is where social features related to the specific users will live, e.g likes and collections, while also showing the username, handle, any links, etc.

Will live under `/profile/<handle>` URL, e.g. `/profile/zeu.dev`

- [ ] `dev.npmx.actor.profile`: modeled after bsky & tangled
- [ ] `/profile/<handle>` route + page