SqlDriverProbe surfaced 'Config JSON is invalid: ' + ex.Message, where
SqlDriverBrowser.ParseDocument deliberately withholds the identical message
because the malformed text may itself carry a connection string. The two read
the same blob shape - the AdminUI Sql picker composes a document with a
top-level connectionString literal - so a malformed paste reaches both. The
probe now reports the failure class only, matching the browser.
Joseph Doherty
073930e023