feat: add REST API (FastAPI) + Dockerfile for containerized deployment

docs: add API verification comments to gemini_client.py

fix: query_engine.py - improve __repr__ null safety

fix: akinator.py - add null safety for caption access

fix: frame_extractor - add max(1,...) guard for frame_interval

fix: update visual_encoders.py - verified API for transformers 5.x (SigLIP2 + Grounding DINO)

Add all remaining modules: index_store, query_engine, akinator, pipeline, app, requirements

Add query engine with boolean ops and fusion

Add Gemini client

Add visual encoders (SigLIP2 + Grounding DINO)

Add frame extractor

Add config module

Add package init