After two years of brutal government repression and destruction of their homeland, the Ngobe Indians of western Panama won a major victory yesterday as the Inter-American Commission on Human Rights called on Panama  to suspend all work on a hydroelectric dam that threatens the Ngobe homeland.  The Chan-75 Dam is being built across the Changuinola River by the government of Panama and a subsidiary of the Virgin-based enery giant AES Corporation.  The Commission's decision was the result of a petition filed last year by the Ngobe, after AES-Changuinola began bulldozing houses and farming plots.  When the Ngobe protested the destruction of their homes, the government sent riot police who beat and arrested villagers, including women and children, and set up a perminent cordon around the community to prevent anyone from entering the area.  In addition to threatening the community, the dam will irreversibly harm the nearby La Amistad UN Biosphere Reserve.