feat: add i18n descriptions to all hands and channels (#22)

Add [i18n.zh], [i18n.zh-TW], [i18n.ja], [i18n.ko], [i18n.de], [i18n.es]
sections with translated descriptions to:
- 15 Hand TOML files (hands/*/HAND.toml)
- 44 Channel TOML files (channels/*.toml)

This enables the website to display localized Hand and Channel descriptions
based on the user's selected language.

channels/discourse.toml

@@ -5,6 +5,24 @@ category = "developer"
 icon = "💬"
 protocol = "rest-api"
 
+[i18n.zh]
+description = "Discourse 论坛适配器，通过 Discourse API 发布主题和回复"
+
+[i18n.zh-TW]
+description = "Discourse 論壇適配器，透過 Discourse API 發布主題和回覆"
+
+[i18n.ja]
+description = "Discourseフォーラムアダプター、Discourse APIを介したトピックと返信の投稿"
+
+[i18n.ko]
+description = "Discourse 포럼 어댑터, Discourse API를 통한 주제 및 답글 게시"
+
+[i18n.de]
+description = "Discourse-Forum-Adapter zum Posten von Themen und Antworten über die Discourse-API"
+
+[i18n.es]
+description = "Adaptador de foro Discourse para publicar temas y respuestas a través de la API de Discourse"
+
 [metadata]
 url = "https://www.discourse.org"
 docs = "https://docs.discourse.org"