Add %check_in_day_of_week% shortcode to match existing %check_out_day_of_week%

Problem Statement:

• The %check_out_day_of_week% shortcode is available for displaying the day of the week for check-out dates
• There is no corresponding %check_in_day_of_week% shortcode for check-in dates
• This creates an inconsistency in available shortcodes

Current Workaround:

• No workaround exists — hosts cannot display the day of the week for check-in dates using shortcodes

Impact:

• Inconsistent shortcode availability between check-in and check-out
• Hosts cannot personalize messages with the check-in day of the week

Proposed Solution:

• Add a %check_in_day_of_week% shortcode that mirrors the functionality of %check_out_day_of_week%

Unlock:

• Hosts would be able to display the day of the week for check-in dates in messages and automations
• Consistent shortcode availability for both check-in and check-out dates