perf(launcher): implement staggered data loading for sessions and presentations

- Optimized session list load to be shell-only, preventing initial request storms.\n- Moved deep data fetching (presenters/files) into the Presentation component level using Svelte effects.\n- Deferred child collection lookups until components are rendered in the DOM.\n- Fixed ae_api import in launcher_presentation_view.\n- Hardened background refresh logic to respect requested views.

src/lib/ae_events/ae_events__event_presentation.ts

@@ -153,9 +153,13 @@ export async function load_ae_obj_li__event_presentation({
                 _refresh_presentation_li_background({ api_cfg, for_obj_type, for_obj_id, inc_file_li, inc_presenter_li, enabled, hidden, view, limit, offset, order_by_li, try_cache, log_lvl: 0 });
                 
                 // Warm cache for nested loads in the background (FIRE AND FORGET)
+                // DEPRECATED Optimization: Don't fire child loads for every item in a list here.
+                // Let the specific Presentation component handle its own children to stagger requests.
+                /*
                 cached_li.forEach(p => {
                     _handle_nested_loads(p, { api_cfg, inc_file_li, inc_presenter_li, enabled, hidden, limit, offset, try_cache, log_lvl: 0 });
                 });
+                */
 
                 return cached_li;
             }