Refactor workweek presets into dedicated manager

Extracts workweek preset logic from ViewManager into WorkweekPresetsManager

Improves separation of concerns by:
- Creating a dedicated manager for workweek preset UI
- Simplifying ViewManager to focus only on view selector
- Implementing event-driven CSS updates
- Reducing code duplication in ConfigManager

Follows "each UI element has its own manager" architectural principle

src/configurations/CalendarConfig.ts

@@ -18,7 +18,7 @@ export const ALL_DAY_CONSTANTS = {
 } as const;
 
 /**
- * Work week presets
+ * Work week presets - Configuration data
  */
 export const WORK_WEEK_PRESETS: { [key: string]: IWorkWeekSettings } = {
   'standard': {
@@ -98,22 +98,13 @@ export class Configuration {
     return Configuration._instance;
   }
 
-
-  // Helper methods
-  getWorkWeekSettings(): IWorkWeekSettings {
-    return WORK_WEEK_PRESETS[this.currentWorkWeek] || WORK_WEEK_PRESETS['standard'];
-  }
-
-  setWorkWeek(workWeekId: string): void {
-    if (WORK_WEEK_PRESETS[workWeekId]) {
-      this.currentWorkWeek = workWeekId;
-      this.dateViewSettings.weekDays = WORK_WEEK_PRESETS[workWeekId].totalDays;
-    }
-  }
-
   setSelectedDate(date: Date): void {
     this.selectedDate = date;
   }
+
+  getWorkWeekSettings(): IWorkWeekSettings {
+    return WORK_WEEK_PRESETS[this.currentWorkWeek] || WORK_WEEK_PRESETS['standard'];
+  }
 }
 
 // Backward compatibility alias