feat: add shared task assignments and quick win sorting

app/forms.py

@@ -48,6 +48,7 @@ class TaskForm(FlaskForm):
     description = TextAreaField("Beschreibung", validators=[Optional(), Length(max=2000)])
     default_points = IntegerField("Punkte", validators=[DataRequired(), NumberRange(min=1, max=500)], default=10)
     assigned_user_id = SelectField("Zugewiesen an", coerce=int, validators=[DataRequired()])
+    assigned_user_secondary_id = SelectField("Zweite Person", coerce=int, validators=[Optional()], default=0)
     due_date = DateField("Fälligkeitsdatum", format="%Y-%m-%d", validators=[DataRequired()])
     recurrence_interval_value = IntegerField(
         "Intervallwert",
@@ -74,6 +75,9 @@ class TaskForm(FlaskForm):
         if self.recurrence_interval_unit.data != "none" and not self.recurrence_interval_value.data:
             self.recurrence_interval_value.errors.append("Bitte gib einen Intervallwert an.")
             return False
+        if self.assigned_user_secondary_id.data and self.assigned_user_secondary_id.data == self.assigned_user_id.data:
+            self.assigned_user_secondary_id.errors.append("Bitte wähle hier eine andere Person oder keine zweite Person.")
+            return False
         return True