K-9 Mail v6.400

What's Changed

• Added swipe actions to the message list screen (@cketti, @Alecaddd)
• Added support for swiping between messages (@andrewfg, @cketti)
• Added a monochromatic app icon for Android 13 (@Sandelinos)
• Fixed "K-9 Accounts" shortcuts (please remove existing shortcuts and add them again) (@cketti)
• Fixed error reporting for (old) send failures (@cketti)
• A lot of other bug fixes; see changes for versions 6.3xx (@rezazarchi, @Croydon, @AoEiuV020, @johnjohndoe, @PatrykMis, @cketti)
• Added Western Frisian translation and updated others (many volunteers via Transifex)

Full Changelog: 6.202...6.400