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/routes/events/[event_id]/(launcher)/launcher_presentation_view.svelte

@@ -7,10 +7,26 @@
 
     import { liveQuery } from 'dexie';
     import { db_events } from '$lib/ae_events/db_events';
-    import { ae_loc } from '$lib/stores/ae_stores';
+    import { ae_loc, ae_api } from '$lib/stores/ae_stores';
     import { events_loc, events_sess } from '$lib/stores/ae_events_stores';
+    import { events_func } from '$lib/ae_events_functions';
     import Event_launcher_file_cont from './launcher_file_cont.svelte';
 
+    // Staggered Load: Trigger deep fetch only when component is active
+    $effect(() => {
+        const id = lq__event_presentation_obj?.event_presentation_id;
+        if (id) {
+            events_func.load_ae_obj_id__event_presentation({
+                api_cfg: $ae_api,
+                event_presentation_id: id,
+                inc_file_li: true,
+                inc_presenter_li: true,
+                try_cache: true,
+                log_lvl: 0
+            });
+        }
+    });
+
     // Event File (Directly linked to presentation)
     let lq__event_file_obj_li = $derived(
         liveQuery(async () => {