fix: restore terminal buffer when switching back to pooled session

Instead of unconditionally resetting the terminal, reused sessions
now restore the saved screen content from the session pool.

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

gui/tabs/terminal_tab.py

@@ -69,7 +69,6 @@ class TerminalTab(ctk.CTkFrame):
 
         alias = self._current_alias
         self._terminal.set_status(t("term_connecting").format(alias=alias), "#ccaa00")
-        self._terminal.reset()
         self._intentional_disconnect = False
 
         def _do_connect():
@@ -81,10 +80,19 @@ class TerminalTab(ctk.CTkFrame):
                     cols, rows = self._terminal.get_size()
                     session, is_new = self.session_pool.get_or_create_shell_session(alias, server, key_path)
                     if is_new:
-                        # Configure the session with proper terminal dimensions
+                        # New session — reset terminal for clean start
+                        self.after(0, self._terminal.reset)
                         session.cols = cols
                         session.rows = rows
                         session.connect()
+                    else:
+                        # Reused session — restore saved buffer instead of resetting
+                        saved_buf = self.session_pool.get_shell_state(alias)
+                        def _restore_buffer():
+                            self._terminal.reset()
+                            if saved_buf:
+                                self._terminal.feed(saved_buf + b"\n")
+                        self.after(0, _restore_buffer)
 
                     # Set up callbacks even if session already existed
                     session.on_data = self._on_data_received
@@ -92,6 +100,7 @@ class TerminalTab(ctk.CTkFrame):
                     self._session = session
                 else:
                     # Legacy behavior without session pool
+                    self.after(0, self._terminal.reset)
                     cols, rows = self._terminal.get_size()
                     session = ShellSession(server, key_path, cols=cols, rows=rows)
                     session.on_data = self._on_data_received