Enhance datepicker UX: position above input with proper styling

- Added CSS positioning to display inline datepicker above input field
- Enhanced datepicker styling with background, border and shadow
- Improved template with datepicker-above class for better positioning
- Maintains Bootstrap 5 compatibility and inline mode functionality

This provides a better user experience by preventing the datepicker
from appearing below and potentially being cut off by page boundaries.

dist/bootstrap5-editable/css/editable-form.css

@@ -151,3 +151,17 @@
 .editable-pre-wrapped {
    white-space: pre-wrap;
 }
+
+/* Position datepicker above input for datepicker-above class */
+.datepicker-above .datepicker-inline {
+   position: absolute;
+   bottom: 100%;
+   left: 0;
+   right: 0;
+   z-index: 1000;
+   margin-bottom: 5px;
+   background: white;
+   border: 1px solid #dee2e6;
+   border-radius: 0.375rem;
+   box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
+}