feat(export): add live preview and configurable export options

feat(hf): prepare video-frame-extractor for Hugging Face Space

feat: update download functionality to allow selection of specific images for download

feat: update README and HTML for improved single video upload and add download all images functionality

feat: add batch export functionality for multiple video files as SVG ZIP

feat: export selected frames as filmstrip-style embedded SVG

chore: switch project run flow to uv run with pyproject dependencies

feat: add minimal web video frame extractor with uniform sampling