Refactor profile-edit, candidate-profile, proposed-candidates, and registration forms

- Added a new div container in profile-edit.php for better layout structure.
- Removed the back button from candidate-profile.php to streamline navigation.
- Updated proposed-candidates.php to open candidate links in a new tab for improved user experience.
- Modified registration forms to make the profile visibility checkbox optional, enhancing user flexibility.

layout/style-scss/style.scss

@@ -306,8 +306,15 @@ ol {
   &.btn-profile {
     float: left;
 
+    @media (max-width: 767px) {
+      float: none;
+      width: 100%;
+      margin-bottom: 10px;
+    }
+
     &.btn-success {
       padding: 15px;
+      white-space: wrap;
     }
   }
 }