Remove mutability

Author: timmo001

src/common/datetime/weekday.ts

@@ -18,7 +18,7 @@ export type WeekdayLong =
   | "friday"
   | "saturday";
 
-export const WEEKDAYS_SHORT: WeekdayShort[] = [
+export const WEEKDAYS_SHORT = [
   "sun",
   "mon",
   "tue",
@@ -28,7 +28,7 @@ export const WEEKDAYS_SHORT: WeekdayShort[] = [
   "sat",
 ] as const;
 
-export const WEEKDAYS_LONG: WeekdayLong[] = [
+export const WEEKDAYS_LONG = [
   "sunday",
   "monday",
   "tuesday",
@@ -46,7 +46,7 @@ export const WEEKDAY_MAP: Record<WeekdayIndex, WeekdayShort> = {
   4: "thu",
   5: "fri",
   6: "sat",
-};
+} as const;
 
 export const WEEKDAY_SHORT_TO_LONG: Record<WeekdayShort, WeekdayLong> = {
   sun: "sunday",
@@ -56,4 +56,4 @@ export const WEEKDAY_SHORT_TO_LONG: Record<WeekdayShort, WeekdayLong> = {
   thu: "thursday",
   fri: "friday",
   sat: "saturday",
-};
+} as const;