Improve error handling, logging

src-tauri/src/slot.rs

@@ -139,9 +139,15 @@ impl Day {
     }
 
     pub fn is_weekend(&self, month: u32, year: i32) -> bool {
-        let date = NaiveDate::from_ymd_opt(year, month, self.0 as u32).unwrap();
-        let weekday = date.weekday();
-        weekday == Weekday::Sat || weekday == Weekday::Sun
+        let date = NaiveDate::from_ymd_opt(year, month, self.0 as u32);
+
+        match date {
+            Some(date) => {
+                let weekday = date.weekday();
+                weekday == Weekday::Sat || weekday == Weekday::Sun
+            }
+            None => false,
+        }
     }
 
     pub fn weekday(&self, month: u32, year: i32) -> Weekday {