code-struc.md

app/
├── main.py                 # FastAPI entry
├── gradio_ui.py            # White-label UI
├── tenants/
│   └── ohamlab.json        # Default tenant config
├── documents/
│   └── ohamlab/
│       ├── general.md
│       └── general-hi.md
├── services/
│   ├── llm.py              # Qwen logic
│   ├── retriever.py        # Embeddings + search
│   ├── tts.py              # Audio generation
│   └── storage.py          # Document handling
├── models/
│   └── tenant.py           # Tenant schema
├── requirements.txt

PDF / MD files
   ↓
Retriever (embeddings + similarity)
   ↓   ← THIS IS WHERE YOU ARE FAILING
Context text
   ↓
Qwen LLM
   ↓
Answer