refactor: remove `defaultFS` from parameters (#841)

.changeset/new-shirts-reply.md

packages/core/src/embeddings/utils.ts

packages/core/src/readers/CSVReader.ts

packages/core/src/readers/DocxReader.ts

packages/core/src/readers/HTMLReader.ts

packages/core/src/readers/ImageReader.ts

packages/core/src/readers/LlamaParseReader.ts

packages/core/src/readers/MarkdownReader.ts

packages/core/src/readers/PDFReader.ts

packages/core/src/readers/SimpleDirectoryReader.edge.ts

packages/core/src/readers/TextFileReader.ts

packages/core/src/readers/type.ts

packages/core/src/storage/FileSystem.ts

packages/core/src/storage/StorageContext.ts

packages/core/src/storage/docStore/SimpleDocumentStore.ts

packages/core/src/storage/docStore/types.ts

packages/core/src/storage/indexStore/SimpleIndexStore.ts

packages/core/src/storage/indexStore/types.ts

packages/core/src/storage/kvStore/SimpleKVStore.ts

packages/core/src/storage/kvStore/types.ts