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_zh.arb

@@ -1335,5 +1335,17 @@
   "listFilter_repeaters": "重复器",
   "listFilter_roomServers": "房间服务器",
   "listFilter_unreadOnly": "未读消息",
-  "listFilter_newGroup": "新组"
+  "listFilter_newGroup": "新组",
+  "channels_joinPrivateChannel": "加入私密频道",
+  "channels_createPrivateChannelDesc": "使用密钥保护。",
+  "channels_joinPrivateChannelDesc": "手动输入密钥。",
+  "channels_createPrivateChannel": "创建私聊频道",
+  "channels_joinPublicChannel": "加入公共频道",
+  "channels_joinPublicChannelDesc": "任何人都可以加入这个频道。",
+  "channels_joinHashtagChannel": "加入标签频道",
+  "channels_joinHashtagChannelDesc": "任何人都可以加入话题频道。",
+  "channels_scanQrCode": "扫描二维码",
+  "channels_scanQrCodeComingSoon": "即将到来",
+  "channels_enterHashtag": "输入标签",
+  "channels_hashtagHint": "例如 #团队"
 }