fix: easter-egg ticker now properly works in Gradio app

feat: WebLLM browser agent with PeerJS mesh, HybridRAG, news signals, and easter-egg ticker

feat: federated RAG + comprehensive security fixes

feat: Nemotron Space, Modal backend, sponsor prize targeting, improvements doc

feat: impl_ref §22 gap-fill — all missing symbols implemented

fix: 0 test failures; FileService; real RagService; emergency probe; chat return

feat: implement all M01-M13, X01-X04 modules + quality gate fixes