[MEDIUM] HomeScreen week calculation uses undefined dueDate

filteredAppointments references dueDate inside .map(). On initial render before fetchData(), dueDate is ''. new Date('') is Invalid Date, weekNumber becomes NaN. All appointments fail filter since NaN > 1 is false.\n\nFile: Frontend/src/Screens/HomeScreen.jsx, lines 94-96\nFix: Guard filter with if (!dueDate) return [] or use loading state