fix: API route security fixes (path traversal, auth, bare except)

- articles.py: Path traversal sanitization
- optimizer_logs.py: Admin auth guard
- platform_config.py: Admin auth guard
- system.py: Path traversal whitelist
- topic_config.py: Admin auth guard
- topics.py: Minor fix

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

platform/backend/app/api/topics.py

@@ -167,7 +167,7 @@ def create_topic(
             try:
                 num = int(max_topic.id[1:]) + 1
                 topic_id = f"T{num:03d}"
-            except:
+            except (ValueError, TypeError):
                 topic_id = f"T{datetime.now().strftime('%m%d%H%M')}"
         else:
             topic_id = f"T{datetime.now().strftime('%m%d%H%M')}"