chore(docker): remove MongoDB service and related configurations from local setup
feat(migrations): create ChapterMeta table and add search_name, size_bytes, mtime_epoch, lastScannedAt, review_status, and review_payload columns to SourceAsset
chore(dependencies): remove motor and pymongo from project dependencies
feat(docker): configure NAS content and EPUB source directories in docker-compose
feat(migrations): add tables for SourceAsset, ImportJob, ChapterContentRef, and AssetNovelMapping
feat(scripts): create backfill script for populating ChapterContentRef from MongoDB chapters