Add Bluesky and Mastodon to author profiles

[michamos]

Users are leaving X/Twitter and want to add alternative social platforms to their user profiles. We should support Bluesky and Mastodon, and rename Twitter to X.

Required parts:

• Review and merge the PR to add them to the schemas in Add Bluesky and Mastodon to ids inspirehep/inspire-schemas#468
• bump inspire-schemas
• Add UI elements on the author pages to display them, like we do for Twitter with appropriate icons. The link targets should be
  • https://bsky.app/user/{value} for bluesky
  • https://{hostname}/@{username} for mastodon (parts before and after the @ in value respectively)
• Add entries to the user submission form so users can add those elements to their profile
• Add a link to follow on Bluesky next to the Twitter link on the homepage (please make it look good 🙂 )
• Change user-facing Twitter references and logos to X (author profiles, submission forms, homepage)