fix: 🐛 解决缺少选中默认主题颜色报错的问题！

Author: limintao

src/CalendarContext.ts

@@ -22,9 +22,7 @@ export interface CalendarContextType extends DatePickerBaseProps {
   onChangeYear: (value: number) => void;
 }
 
-const CalendarContext = createContext({
-  theme: { selectedItemColor: '#0047FF' },
-} as CalendarContextType);
+const CalendarContext = createContext({} as CalendarContextType);
 
 export const useCalendarContext = () => useContext(CalendarContext);
 

src/DateTimePicker.tsx

@@ -431,7 +431,7 @@ const DateTimePicker: React.FC<
       displayFullDays,
       firstDayOfWeek: firstDay,
       height,
-      theme: rest,
+      theme: { selectedItemColor: '#0047FF', ...rest },
     }),
     [
       columns,

src/utils.ts

@@ -350,7 +350,10 @@ export const isEqual = (value: any, other: any) => {
  * @returns {string} The color string with alpha channel.
  * @throws {Error} If the color format is not supported.
  */
-export const addColorAlpha = (color: string, alpha: number = 1): string => {
+export const addColorAlpha = (
+  color: string = '#0047FF',
+  alpha: number = 1
+): string => {
   const a = clamp01(alpha);
   const input = color.trim();