Remediate the 2026-09-03 feature-test findings

plugins/knowledgebase/api/routes.py

@@ -4,6 +4,7 @@ from flask import Blueprint, request
 from flask_jwt_extended import jwt_required
 
 from shopdb.api import (
+    intarg,
     db,
     Application,
     success_response,
@@ -16,7 +17,7 @@ from shopdb.api import (
 
 from ..models import KnowledgeBase
 
-from shopdb.api import require_permission, apply_import_timestamps
+from shopdb.api import require_permission, apply_import_timestamps, intarg
 
 knowledgebase_bp = Blueprint('knowledgebase', __name__)
 
@@ -91,8 +92,8 @@ def list_articles():
         query = query.filter(_search_clause(search))
 
     # Filter by topic/application
-    if appid := request.args.get('appid'):
-        query = query.filter(KnowledgeBase.appid == int(appid))
+    if (appid := intarg('appid')) is not None:
+        query = query.filter(KnowledgeBase.appid == appid)
 
     # Exact-match natural-key lookups for idempotent import. linkurl is the
     # stable natural key; shortdescription (the title) is offered as a fallback.