fix(i18n): say which request the server answered unexpectedly

"the server answered a machine tree with {reply}" reads as though a machine
tree was the thing answered. It is the request that was for the machine
tree, and the reply is whatever came back instead.

The Chinese translator had already worked this out and supplied the missing
word -- "回复了机器树请求" says "replied to the machine-tree request" -- so
zh needed no change. English and Japanese carried the ambiguity.

src/ui/i18n/en.rs

@@ -1296,7 +1296,7 @@ pub fn translate_en(key: L10nKey) -> &'static str {
         }
         L10nKey::RemoteNoRouteToHost => "tty7 no longer has a way to reach {machine}",
         L10nKey::RemoteMachineTreeUnexpectedReply => {
-            "the server answered a machine tree with {reply}"
+            "the server answered the machine-tree request with {reply}"
         }
         L10nKey::RemoteMismatchVersionFromExe => "{version} (from {exe})",
         L10nKey::AppNoRunningCodingAgent => {

src/ui/i18n/ja.rs

@@ -1327,7 +1327,7 @@ pub fn translate_ja(key: L10nKey) -> Option<&'static str> {
         }
         L10nKey::RemoteNoRouteToHost => "tty7 は {machine} に到達する手段を失いました",
         L10nKey::RemoteMachineTreeUnexpectedReply => {
-            "サーバーがマシンツリーに {reply} で応答しました"
+            "サーバーがマシンツリー要求に {reply} で応答しました"
         }
         L10nKey::RemoteMismatchVersionFromExe => "{version}（{exe} から）",
         L10nKey::AppNoRunningCodingAgent => {