gtk: add window title renaming (#10999)

Fixes #10469 for GTK.

include/ghostty.h

@@ -682,6 +682,7 @@ typedef struct {
 typedef enum {
   GHOSTTY_PROMPT_TITLE_SURFACE,
   GHOSTTY_PROMPT_TITLE_TAB,
+  GHOSTTY_PROMPT_TITLE_WINDOW,
 } ghostty_action_prompt_title_e;
 
 // apprt.action.Pwd.C
@@ -937,6 +938,7 @@ typedef enum {
   GHOSTTY_ACTION_DESKTOP_NOTIFICATION,
   GHOSTTY_ACTION_SET_TITLE,
   GHOSTTY_ACTION_SET_TAB_TITLE,
+  GHOSTTY_ACTION_SET_WINDOW_TITLE,
   GHOSTTY_ACTION_PROMPT_TITLE,
   GHOSTTY_ACTION_PWD,
   GHOSTTY_ACTION_MOUSE_SHAPE,