refactor(events): harden V3 String-Only ID vision and fix Session Alert store error

- Standardized Event module logic files to strictly use random string IDs, ensuring frontend consistency and avoiding 'Integer Trap' 404s.
- Refactored 'ae_comp__event_session_alert.svelte' to accept a plain object instead of a store/observable, resolving the 'store_invalid_shape' error in list loops.
- Updated all callers of the alert component to pass unwrapped session objects.
- Cleaned up event-related UI components to remove redundant '_random' field lookups and align with V3 CRUD patterns.
- Updated project metadata (GEMINI.md, TODO.md) to reflect the new memory structure and latest hardened state.

src/routes/events/[event_id]/event_page_menu.svelte

@@ -178,7 +178,7 @@
                                 .update_ae_obj_id_crud_v2({
                                     api_cfg: $ae_api,
                                     object_type: 'event',
-                                    object_id: $lq__event_obj?.event_id_random,
+                                    object_id: $lq__event_obj?.event_id,
                                     object_reload: true,
                                     field_name: 'alert',
                                     new_field_value: new_alert_value,