feat(hosted-files): introduce standardized download component and V3 action support

- Created AE_Comp_Hosted_Files_Download_Button using Svelte 5 and Lucide icons.
- Added file_extension_icon_lucide utility for direct Lucide icon mapping.
- Refactored download logic to core__hosted_files.ts using V3 Action endpoint (/v3/action/hosted_file/.../download).
- Integrated new component into Event File Object Table.
- Cleaned up legacy window.postMessage calls in several file management views.

NOTE: The new download component is currently in development and may not be fully functional.

src/lib/ae_utils/ae_utils.ts

@@ -8,6 +8,7 @@ import {
 } from './ae_utils__files';
 import { get_obj_li_w_match_prop } from './ae_utils__get_obj_li_w_match_prop';
 import { file_extension_icon } from './ae_utils__file_extension_icon';
+import { file_extension_icon_lucide } from './ae_utils__file_extension_icon_lucide';
 import { process_permission_checks } from './ae_utils__perm_checks';
 import { iso_datetime_formatter } from './ae_utils__datetime_format';
 import { is_datetime_recent } from './ae_utils__is_datetime_recent';
@@ -337,6 +338,7 @@ export const ae_util = {
     shorten_string: shorten_string,
     shorten_filename: shorten_filename,
     file_extension_icon: file_extension_icon,
+    file_extension_icon_lucide: file_extension_icon_lucide,
     format_html: format_html,
     set_obj_prop_display_name: set_obj_prop_display_name,
     return_obj_type_path: return_obj_type_path,