Multimodal KS

[HARSHDIPSAHA]

Fixes issue #16
Currently, the KnowledgeSpace AI agent relies only on text-based queries, while a large amount of
neuroscience metadata remains locked inside non-editable formats such as figures, tables, and
presentation screenshots. This PR introduces a multimodal pipeline that allows users to upload
images and automatically convert them into refined, high-signal search queries.

The feature includes:

• A React-based upload interface with an auto-expanding search box for long scientific queries.
• A FastAPI backend endpoint that performs OCR using Pytesseract.
• An intelligence layer using Gemini 2.0 Flash-Lite for zero-shot Named Entity Recognition (NER).
• A refined prompt that outputs only a clean, comma-separated list of scientific entities,
  preventing conversational noise from polluting the search engine.

Impact:

• Unlocks neuroscience metadata trapped in images.
• Improves dataset discovery precision and recall.
• Enables a fully multimodal search workflow for KnowledgeSpace.

[HARSHDIPSAHA]

@QuantumByte-01 please review.