Version 6.6.1 - AI-KM: Agent skills and ontology-driven knowledge modeling

This update introduces two significant capabilities: an agentic skill framework and ontology-driven knowledge modeling with retrieval. The agentic skill framework encapsulates complex AI behaviors as reusable, conversation-invokable skills, supporting both predefined expert skills and an autonomous planning mode for novel tasks. Meanwhile, the ontology-driven knowledge modeling module elevates knowledge representation from simple slice structures to formal, machine-interpretable ontologies built through natural language entity extraction. These advances enable domain experts to encode their expertise as both executable skills and structured knowledge, creating a closed loop where knowledge is represented as formal structure and applied as dynamic process.