fix: improve element label positioning and state management

- Fix element label positioning using getBoundingClientRect + scroll offset
- Filter out state classes from element selectors (element-hovered, etc.)
- Add cursor pointer on hovered elements and pages
- Prevent elements from having both hovered and selected classes
- Fix issue where closing popup left previous element in hovered state

Ensures only one visual state per element at a time and cleaner
selector display in labels.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

public/assets/css/pagedjs-interface.css

@@ -147,6 +147,7 @@
 /* Hover and selection states for pages and elements */
 .page-hovered {
   outline: 2px solid #ff8a5050 !important;
+  cursor: pointer !important;
 }
 
 .page-selected {
@@ -155,6 +156,7 @@
 
 .element-hovered {
   outline: 2px solid #7136ff50 !important;
+  cursor: pointer !important;
 }
 
 .element-selected {