Improves drag and drop event handling

Refactors drag and drop logic for better event handling and code clarity.

- Moves drag styling to CSS class for cleaner code.
- Emits a 'drag:convert-from-allday' event to handle the conversion of all-day events back to day events.
- Adds logging for debugging purposes.

wwwroot/css/calendar-events-css.css

@@ -51,6 +51,18 @@ swp-day-columns swp-event {
     color: var(--color-text);
   }
   
+  /* Dragging state */
+  &.dragging {
+    position: absolute;
+    z-index: 999999;
+    pointer-events: none;
+    opacity: 0.8;
+    left: 2px;
+    right: 2px;
+    margin-left: 0px;
+    width: auto;
+  }
+  
 }
 
 swp-day-columns swp-event:hover {