A COMPREHENSIVE STUDY OF AGENTIC AI SYSTEMS: EXPLORING THE EVOLUTION FROM PREDICTIVE MACHINE LEARNING MODELS TO AUTONOMOUS, GOAL-DIRECTED, AND DECISION-MAKING ARTIFICIAL AGENTS IN COMPLEX ENVIRONMENTS. J. Integr. Sci. Soc. Impact. 2026;2(1):91-100. doi:10.29121/JISSI.v2.i1.2026.37