Add support for private and hashtag channels in localization and channel management

- Updated Polish, Portuguese, Slovak, Slovenian, Swedish, and Chinese localization files to include new strings for creating and joining private channels, as well as joining hashtag channels.
- Enhanced the channel management UI to allow users to create and join private channels, join public channels, and join channels via hashtags.
- Implemented PSK derivation from hashtags using SHA256 in the Channel model.
- Improved the translation script to handle missing keys and translate all locales efficiently.

lib/l10n/app_sk.arb

@@ -1335,5 +1335,17 @@
   "listFilter_repeaters": "Opakovadlá",
   "listFilter_roomServers": "Servéry miestnosti",
   "listFilter_unreadOnly": "Nezaregistrované len",
-  "listFilter_newGroup": "Nová skupina"
+  "listFilter_newGroup": "Nová skupina",
+  "channels_createPrivateChannel": "Vytvorte súkromný kanál",
+  "channels_joinPrivateChannel": "Pripojiť sa k súkromnému kanálu",
+  "channels_joinPrivateChannelDesc": "Ručne zadajte tajný kľúč.",
+  "channels_createPrivateChannelDesc": "Zabezpečené pomocou tajného kľúča.",
+  "channels_joinPublicChannel": "Pripojte sa k verejnému kanálu",
+  "channels_joinPublicChannelDesc": "Któvek sátó na tutó kanalizovát.",
+  "channels_joinHashtagChannel": "Pripojte sa k Hashtag Kanálu",
+  "channels_joinHashtagChannelDesc": "Ktoekolikoľvek sa môže pridať do hashtag kanálov.",
+  "channels_scanQrCode": "Skenujte QR kód",
+  "channels_scanQrCodeComingSoon": "Čoskoro",
+  "channels_enterHashtag": "Zadajte hashtag",
+  "channels_hashtagHint": "napr. #tím"
 }