Added database upload feature (db_uploader) Allows user to upload .db/.sqlite or schema.json files and extract schema automatically.

[taghreed1kh]

I added a new Streamlit feature called Database Uploader.
It allows the user to upload SQLite database files (.db / .sqlite) or schema.json files.

When a .db file is uploaded, the app automatically extracts the schema using the extract_sqlite_schema function.
When a JSON schema file is uploaded, it is displayed and saved for later use.

✅ Added files:

streamlit_app/db_uploader.py

streamlit_app/db_fetcher.py

streamlit_app/init.py

✅ Purpose:
This helps users easily upload and view database schemas directly inside the Streamlit app.