New Jersey “Gold Coast” developer Fred Daibes has pleaded guilty to taking part in an insider loan scam at Mariner’s Bank, the financial institution that he founded and where he served as chairman of the board of directors. Daibes, the Edgewater-based developer whose glitzy projects have transformed the Hudson River waterfront, appeared in U.S. District Court by Zoom on Thursday and pleaded guilty to one count of concealing a $1.8 million bank loan made to him. In exchange for the guilty plea, the government agreed to drop the remaining 13 counts in the indictment and won’t seek a prison term …