feat: upgrade agent to llama-3.3-70b

feat: add backtest target date selector

fix: switch to llama-3.1-8b-instant and build frontend/dist to serve new ui changes

fix: switch LLM from llama-3.3-70b to llama3-8b-8192 to bypass daily Groq token limits

chore: increase celery soft time limit for chronos ensemble cpu inference

chore: use llama-3.3-70b-versatile for Groq API

feat: switch LLM to openai/gpt-oss-120b (Groq's strongest free-tier model at 120B params)

feat: upgrade LLM to Llama 4 Maverick, overhaul prompts with anti-slop rules, fix event card labels, enrich demo data

fix: comprehensive production stability fixes

Feat/Chronos-2 Integrated,Tests added,Finetuned

UI added and fixed

7 nodes implementation done