Add support to show dayOfWeek

**Is your feature request related to a problem? Please describe.**

The feature should provide the dayOfWeek for a given date

**Describe the solution you'd like**

Given a date (not the timestamp part), the feature should provide the day of the week -> dayOfWeek(input, format)
Open to other suggestions for the syntax
Format:
MM/dd/yyyy
yyyyMMdd
yyyy-MM-dd

Review the existing expression-language functions and date handling to determine where a dayOfWeek(input, format) function belongs. Check the requested formats—MM/dd/yyyy, yyyyMMdd, and yyyy-MM-dd—and confirm that the result uses only the date portion. Done means a chosen syntax supports each listed format and returns the correct weekday.

Written by the indexing model from the issue text.