Enhance: Implement exhaustive background caching and recursive data loading

- Implemented aggressive room-wide background caching engine in LauncherBackgroundSync.svelte.
- Added inc_file_li and inc_all_file_li support to Event and Event Location object loaders for total room coverage.
- Switched to proven V1 download path (/hosted_file/) to resolve V3 CRUD binary delivery issues.
- Optimized Electron bridge with download locking and flat-hash storage matching legacy 'perfect' logic.
- Standardized all Electron IPC methods and parameters to snake_case.
- Added visual sync progress indicator for room caching status.

src/lib/ae_events/ae_events__event.ts

@@ -10,6 +10,7 @@ import { load_ae_obj_li__event_device } from './ae_events__event_device';
 import { load_ae_obj_li__event_location } from './ae_events__event_location';
 import { load_ae_obj_li__event_session } from './ae_events__event_session';
 import { load_ae_obj_li__event_badge_template } from '$lib/ae_events/ae_events__event_badge_template';
+import { load_ae_obj_li__event_file } from '$lib/ae_events/ae_events__event_file';
 
 const ae_promises: key_val = {};
 

src/lib/ae_events/ae_events__event_location.ts

@@ -4,6 +4,7 @@ import { api } from '$lib/api/api';
 import { db_save_ae_obj_li__ae_obj } from '$lib/ae_core/core__idb_dexie';
 import { db_events } from '$lib/ae_events/db_events';
 import type { ae_EventLocation } from '$lib/types/ae_types';
+import { load_ae_obj_li__event_file } from '$lib/ae_events/ae_events__event_file';
 
 const ae_promises: key_val = {};
 
@@ -12,12 +13,18 @@ export async function load_ae_obj_id__event_location({
     api_cfg,
     event_location_id,
     view = 'default',
+    inc_file_li = false,
+    inc_session_li = false,
+    inc_all_file_li = false,
     try_cache = true,
     log_lvl = 0
 }: {
     api_cfg: any;
     event_location_id: string;
     view?: string;
+    inc_file_li?: boolean;
+    inc_session_li?: boolean;
+    inc_all_file_li?: boolean;
     try_cache?: boolean;
     log_lvl?: number;
 }): Promise<ae_EventLocation | null> {
@@ -58,7 +65,11 @@ export async function load_ae_obj_id__event_location({
         }
     }
 
-    return ae_promises.load__event_location_obj || null;
+    if (!ae_promises?.load__event_location_obj) {
+        return null;
+    }
+
+    return await _handle_nested_loads(ae_promises.load__event_location_obj, { api_cfg, inc_file_li, log_lvl });
 }
 
 // Updated 2026-01-20 to V3
@@ -66,6 +77,7 @@ export async function load_ae_obj_li__event_location({
     api_cfg,
     for_obj_type = 'event',
     for_obj_id,
+    inc_file_li = false,
     enabled = 'enabled',
     hidden = 'not_hidden',
     limit = 100,
@@ -82,6 +94,7 @@ export async function load_ae_obj_li__event_location({
     api_cfg: any;
     for_obj_type?: string;
     for_obj_id: string;
+    inc_file_li?: boolean;
     enabled?: 'enabled' | 'all' | 'not_enabled';
     hidden?: 'hidden' | 'all' | 'not_hidden';
     limit?: number;
@@ -136,9 +149,35 @@ export async function load_ae_obj_li__event_location({
         }
     }
 
+    if (ae_promises.load__event_location_obj_li) {
+        for (const location of ae_promises.load__event_location_obj_li) {
+            await _handle_nested_loads(location, { api_cfg, inc_file_li, log_lvl });
+        }
+    }
+
     return ae_promises.load__event_location_obj_li || [];
 }
 
+/**
+ * Handle nested data loads for a single location object.
+ */
+async function _handle_nested_loads(location_obj: any, { api_cfg, inc_file_li, log_lvl }: any) {
+    const current_location_id = location_obj.event_location_id_random || location_obj.event_location_id || location_obj.id;
+
+    if (inc_file_li) {
+        location_obj.event_file_li = await load_ae_obj_li__event_file({
+            api_cfg,
+            for_obj_type: 'event_location',
+            for_obj_id: current_location_id,
+            enabled: 'all',
+            limit: 25,
+            log_lvl
+        });
+    }
+
+    return location_obj;
+}
+
 // Updated 2026-01-20 to V3
 export async function create_ae_obj__event_location({
     api_cfg,