refactor logging in MonthMenu and TimeStepper components to use console.error for NaN emissions

frontend/src/components/MonthMenu.vue

@@ -31,7 +31,7 @@ const dropdownRef = ref(null)
 const loading = ref(false)
 
 const select = async (newMonth) => {
-  console.log('newMonth: ', newMonth)
+  // console.log('newMonth: ', newMonth)
   showMenu.value = false
   loading.value = true
 

frontend/src/components/TimeStepper.vue

@@ -64,7 +64,7 @@ const hour = computed({
     // console.log('Hour computed. h:', hourVal, 'm: ', m)
 
     if (typeof newVal !== 'number' || isNaN(newVal)) {
-      console.log('Hour emit NaN')
+      console.error('Hour emit NaN')
       emit('update:time', NaN)
     } else {
       emit('update:time', `${String(hourVal).padStart(2, '0')}:${m}`)
@@ -84,7 +84,7 @@ const minute = computed({
     // console.log('Minute computed. h:', h, 'm: ', minuteVal)
 
     if (typeof newVal !== 'number' || isNaN(newVal)) {
-      console.log('Minute emit NaN')
+      console.error('Minute emit NaN')
       emit('update:time', NaN)
     } else {
       emit('update:time', `${h}:${String(minuteVal).padStart(2, '0')}`)