Add basic fast search engine

[aeirya]

available algorithms:

• TF-IDF
• SBERT

how to use:

from search_engine import SearchEngine
from database import get_selected_nodes as id2doc

ids = search.query('a sample query text')
print(id2doc(ids))

ids = search.related_docs(doc_id= 1)
print(id2doc(ids))

[itsalirezam]

[aeirya]

Fixed.