Potential fix for code scanning alert no. 22: Information exposure through an exception

[Rootless-Ghost]

Potential fix for https://github.com/Rootless-Ghost/SigmaForge/security/code-scanning/22

In general, to fix information exposure through exceptions, avoid returning raw exception messages or stack traces to the client. Instead, log detailed errors on the server and respond with a generic, user-friendly message that does not reveal internal implementation details.

For this specific case, the best fix is to change the except ValueError as e: handler in api_template so it does not include str(e) in the JSON response. Instead, return a generic error such as "Template not found." or "Invalid template key." that preserves existing behavior semantics (a 404 for client error) without leaking exception details. Optionally, log the actual exception using the existing logging module for diagnostics. Concretely:

• In app.py, in api_template, lines 149–150, replace return jsonify({"success": False, "error": str(e)}), 404 with a generic message, e.g. return jsonify({"success": False, "error": "Template not found."}), 404.
• Optionally extend that block to log the ValueError via logging.warning or logging.exception, but this is not strictly required to remove the information exposure. The logging import already exists, so no new imports are needed.
  No other parts of the file need changes to fix this specific CodeQL alert.

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