refactor(docs): reorganize docs by type and locale

docs/channels/matrix/README.fr.md

@@ -1,4 +1,4 @@
-> Retour au [README](../../../README.fr.md)
+> Retour au [README](../../project/README.fr.md)
 
 # Guide de configuration du canal Matrix
 

docs/channels/matrix/README.ja.md

@@ -1,4 +1,4 @@
-> [README](../../../README.ja.md) に戻る
+> [README](../../project/README.ja.md) に戻る
 
 # Matrix チャンネル設定ガイド
 

docs/channels/matrix/README.pt-br.md

@@ -1,4 +1,4 @@
-> Voltar ao [README](../../../README.pt-br.md)
+> Voltar ao [README](../../project/README.pt-br.md)
 
 # Guia de Configuração do Canal Matrix
 

docs/channels/matrix/README.vi.md

@@ -1,4 +1,4 @@
-> Quay lại [README](../../../README.vi.md)
+> Quay lại [README](../../project/README.vi.md)
 
 # Hướng dẫn Cấu hình Kênh Matrix
 

docs/channels/matrix/README.zh.md

@@ -1,4 +1,4 @@
-> 返回 [README](../../../README.zh.md)
+> 返回 [README](../../project/README.zh.md)
 
 # Matrix 通道配置指南