v1.9.27: add disconnect button in terminal + disconnect in context menu

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gui/tabs/files_tab.py

@@ -318,6 +318,10 @@ class FilesTab(ctk.CTkFrame):
         if self._current_alias and not self._sftp:
             self._connect_sftp()
 
+    def disconnect(self):
+        """Disconnect SFTP and update UI (called by app)."""
+        self._disconnect_sftp()
+
     # ── SFTP connection ──
 
     def _connect_sftp(self):