Update README with image and project objective

Added an image to the README and clarified the API's purpose.

Author: dsapandora

README.md

@@ -4,6 +4,9 @@ REST API to **index** and **query** documents in a vector database: k-Nearest Ne
 
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+<img width="1426" height="827" alt="Captura de pantalla 2026-01-30 a las 14 33 51" src="https://github.com/user-attachments/assets/4876a949-dada-4530-8cbd-051d20c36596" />
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 ## Objective
 
 Develop a REST API that allows users to index and query their documents within a Vector Database. The API is containerized in a Docker container.