Use Qwen2.5-7B for all agents to resolve stability issues

requirements.txt updated

Use standard Qwen-7B model to avoid 401 routing issues and fix callback signatures

Fix UI endpoint errors and duplicate callback targets

Complete refactor of app.py state to dictionary

Fix return value counts and remove truststore for HF stability

Add demo.queue() and conditional truststore injection to fix HF deployment errors

Replace gr.Sidebar with gr.Column layout for better compatibility

pipeline working