feat(undo): 添加撤销/重做的中英文翻译

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

po/en_US.po

@@ -56,6 +56,14 @@ msgstr "Move Down"
 msgid "Clean Invalid"
 msgstr "Clean Invalid"
 
+#: src/ui/main_window.c
+msgid "Undo"
+msgstr "Undo"
+
+#: src/ui/main_window.c
+msgid "Redo"
+msgstr "Redo"
+
 #: src/ui/main_window.c
 msgid "OK"
 msgstr "OK"
@@ -364,6 +372,14 @@ msgstr "Are you sure you want to continue?"
 msgid "Cleanup completed! Removed %d invalid or duplicate paths."
 msgstr "Cleanup completed! Removed %d invalid or duplicate paths."
 
+#: src/controller/callbacks_nav.c
+msgid "Undo completed"
+msgstr "Undo completed"
+
+#: src/controller/callbacks_nav.c
+msgid "Redo completed"
+msgstr "Redo completed"
+
 #: src/controller/callbacks_basic.c
 msgid "New Environment Variable"
 msgstr "New Environment Variable"