fix: remove account_id injection from nested POST handler

Child objects in the nested endpoint inherit account context from their
parent via the FK relationship and do not carry their own account_id
column (e.g. event_badge, journal_entry). Injecting account_id into
data_to_insert would cause INSERT failures for any child whose table
has no account_id column but whose model has the field (from the view).

The original code set account_id in obj_data before model instantiation,
where the root_validator immediately stripped it — a harmless no-op.
The previous commit turned that dead line into a live injection by moving
it after serialization, which would break journal_entry creates on
non-bypass auth. Removed entirely.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/routers/api_crud_v3_nested.py

@@ -330,18 +330,11 @@ async def post_child_obj(
     # (Matches the flat V3 POST pattern in api_crud_v3.py.)
     sanitize_payload(data_to_insert, input_model, ignore_extra=x_ae_ignore_extra_fields)
 
-    # Enforce account ownership AFTER sanitize_payload so the integer account_id goes
-    # straight to the DB without conflicting with Vision ID string constraints in the model.
-    # Guard: skip if the model explicitly excludes account_id from DB writes (e.g. event_badge,
-    # event_device — the column does not exist in those tables).
-    if not account.super and account.auth_method != 'bypass' and account.account_id:
-        if 'account_id' in input_model.__fields__:
-            excluded = getattr(input_model, 'fields_to_exclude_from_db', [])
-            if 'account_id' not in excluded:
-                data_to_insert['account_id'] = account.account_id
-
     # Re-inject parent FK last — overrides anything sanitize_payload or the model may have
     # set — ensuring the child is always linked to the correct parent.
+    # Note: account_id is intentionally NOT injected here. Child objects in the nested
+    # endpoint inherit account context from their parent via the FK relationship; they do
+    # not carry their own account_id column (e.g. event_badge, journal_entry).
     data_to_insert[f'{parent_obj_type}_id'] = resolved_parent_id
 
     if sql_insert_result := sql_insert(data=data_to_insert, table_name=table_name_insert):