Mention Bluesky in contacts.

README.md

@@ -34,8 +34,7 @@ right away!
 -   E-mail — info@magnum.graphics
 -   Google Groups mailing list — magnum-engine@googlegroups.com
     ([archive](https://groups.google.com/forum/#!forum/magnum-engine))
--   Twitter — https://twitter.com/czmosra and the
+-   Bluesky — https://bsky.app/profile/mosra.cz
-    [#MagnumEngine](https://twitter.com/hashtag/MagnumEngine) hashtag
 
 See also the Magnum Project [Contact & Support page](https://magnum.graphics/contact/)
 for further information.

doc/python/pages/index.rst

@@ -65,8 +65,7 @@ right away!
 -   E-mail --- info@magnum.graphics
 -   Google Groups mailing list --- magnum-engine@googlegroups.com
     (`archive <https://groups.google.com/forum/#!forum/magnum-engine>`_)
--   Twitter --- https://twitter.com/czmosra and the
+-   Bluesky --- https://bsky.app/profile/mosra.cz
-    `#MagnumEngine <https://twitter.com/hashtag/MagnumEngine>`_ hashtag
 
 See also the `Contact & Support page <https://magnum.graphics/contact/>`_ on
 the project website for further information.