Observed behavior:

• When copying a survey with the new copy flow, rows from {{plugin_settings}} where model='Survey' and
  model_id=<source sid> are not recreated for the destination survey.

• As a result, plugins that store per-survey settings through DbStorage lose their configuration on copied
  surveys until settings are manually re-saved.

  Expected behavior:

• Copying a survey should also copy its survey-scoped plugin settings to the new survey, matching the behavior
  from 6.16.4.

  Regression details:

• In 6.16.4, survey copy used surveyGetXMLData(...) + XMLImportSurvey(...), and that path explicitly exported/
  imported survey plugin settings.

• In 6.16.5, the new CopySurvey service replaced that flow, but CopySurvey::copy() does not copy PluginSetting
  rows.

  Impact:

• Any plugin using survey-level DbStorage settings is affected.

• Example symptom: copied surveys appear to have plugin defaults or empty plugin settings instead of
  inheriting the source survey configuration.

  Likely fix:

• Extend CopySurvey to clone PluginSetting rows for model='Survey' from source SID to destination SID as part
  of the copy service.