Enable or disable storing and serving the free-text reason on coding-assistant session attributions for this tenant. Defaults to disabled.

While disabled, a POST to the session attribution endpoint that carries a reason still succeeds and still records the attribution: the server stores null for the text and sets detailTextSuppressed on the response so the caller knows its note was not kept. The GET never returns the text while the switch is off, which means turning it off takes effect on the read path immediately. It does NOT delete free text already stored; that needs a separate sweep. Structured attribution (ticket, source, subscriber, repository, branch, timing) is unaffected in either state.