feat: launch Protect Today from deadline reminders (Closes #723)

src/push_notifications.py

@@ -352,6 +352,7 @@ async def _dispatch_deadline_reminders_unlocked(
                 "title": f"{due_count} deadline{'s' if due_count != 1 else ''} need{'s' if due_count == 1 else ''} attention",
                 "body": f"Open Agenda to review or replan {'it' if due_count == 1 else 'them'}.",
                 "route": "#/my-work/agenda",
+                "protect_route": "#/my-work/agenda/protect-today",
                 "tag": f"stackchain-deadline-digest-{local_day}",
                 "deadline_count": due_count,
             }, separators=(",", ":"))