Strip whitespace from Neo4j credentials — secrets had leading spaces

Add credential debug info to diagnose auth failure

Fix Neo4j default username to 61885e62 (AuraDB instance ID)

Add Neo4j config debug info to Recommend tab

Show actual Neo4j errors instead of silently returning empty

Show Neo4j errors in Recommend tab for debugging

Fix Neo4j username to use env var instead of hardcoded 'neo4j'

Make Neo4j connection graceful — app works even if Neo4j is down

Add full app source code and configs for Streamlit deployment

Duplicate from streamlit/streamlit-template-space