Remove source citation from answers

Fix: straight edge reflect->END, fix stream dedup, heuristic reflect v3

Fix: disable LLM reflection loop, increase top_k to 6, heuristic grounding check

Fix: improve system prompt to not false-negative when answer is in context

Fix: strip non-ASCII chars before sending to llama-server

Fix: remove --flash-attn flag, increase timeout to 300s

Upload agent.py