Plan Detail Start and End Dates

Improved Plan Detail Visibility:** 1/ New Date Fields for Support Categories: We've added `plan_detail_start` and `plan_detail_end` date fields to the "Add Support" and "Edit Support Purpose" modals, allowing you to define specific date ranges for your budget categories. 2/ Dates in DataTables: The "Core Support", "Capital Support", and "Capacity Building" DataTables now display these new `plan_detail_start` and `plan_detail_end` columns, formatted as `DD-MM-YYYY`, giving you a clearer overview of your budget periods.