fixed indexing error, added instruction prompt to model, updated vector db creation, added input rails, made output correctness rail less strict, adapted output on failed output guardrails, added missing requirements

added params for easy experiment execution (see use case)

fixed language check and hallu check, added language check to input rails, fixed email sanitize, removed dummy relevance score, refactorings, fixed requirements for installments, refactored model initialization, adapted CLI output

merged with main

add output guard rails and model text generation

feat: Integrate backend modules into Streamlit app

feat: Set up initial project structure and database script

minimal frontend