refactor: standardize 'prevent_default' helpers and batch format modules

- Renamed internal 'preventDefault' helpers to 'prevent_default' for project-wide snake_case consistency.
- Corrected native event method calls from 'prevent_default()' to 'preventDefault()' to resolve runtime TypeErrors.
- Applied batch formatting (printWidth: 80) to Journals and IDAA Recovery Meetings modules.
- Removed deprecated 'preventDefault' imports from svelte/legacy.
- Fixed Journal Entry 404 by migrating loader to V3 API helper.

src/routes/journals/[journal_id]/+layout.svelte

@@ -116,7 +116,7 @@
                     window.open('/journals');
                     // } else {
                     //     // Left click - toggle menu
-                    //     event.prevent_default(); // Prevent default middle-click behavior
+                    //     event.preventDefault(); // Prevent default middle-click behavior
                     //     show_menu__all_journals = !show_menu__all_journals;
                 }
             }}