fix: exclude account_id and virtual fields from archive_content DB writes

- Adds fields_to_exclude_from_db to Archive_Content_Base to prevent SQL errors on non-existent columns.
- Updates documentation for V3 Create/Update patterns and the x-ae-ignore-extra-fields header.
- Propagates account_id_random to hosted file and media processing methods.

app/routers/hosted_file.py

@@ -276,6 +276,7 @@ async def convert_file(
             link_to_type = link_to_type,
             link_to_id = lid_int,
             account_id = commons.x_account_id,
+            account_id_random = commons.x_account_id_random,
             filename_no_ext = filename_no_ext,
             to_type = to_type
         )
@@ -306,6 +307,7 @@ async def clip_video(
             start_time = start_time,
             end_time = end_time,
             account_id = commons.x_account_id,
+            account_id_random = commons.x_account_id_random,
             link_to_type = link_to_type,
             link_to_id = lid_int,
             filename_no_ext = filename_no_ext,