feat(match): normalize player lists before updating match data

- Added a `normalizeList` function to filter out duplicates and invalid entries from player arrays.
- Updated the match update logic to use normalized player lists for `playersReady`, `playersPlanned`, and `playersPlayed`.
- Enhanced error handling in the ScheduleView to throw an error for failed match updates based on response status.

frontend/src/views/ScheduleView.vue

@@ -502,6 +502,9 @@ export default {
                     playersPlanned,
                     playersPlayed
                 });
+                if (response.status >= 400) {
+                    throw new Error(response?.data?.error || 'Failed to update match players');
+                }
                 console.log('[savePlayerSelection] API response:', response);
                 
                 // Update local match data