AREA: Weather Temperature < Threshold → Discord Alert

Display a pop up allowing the user to configure a temperature alert and send it in Discord

- [ ] Title: “Cold Temperature Alert”
- [ ] Add text field: City or GPS Coordinates
- [ ] Add number field: Temperature Threshold
- [ ] Add text field: Discord Webhook URL
- [ ] Add preview: “Temperature has dropped below X°C!”
- [ ] Add Save button