initial nodev3 work

apps/simple/index.ts

apps/simple/lowlevel.ts

packages/core/src/BaseIndex.ts

packages/core/src/Document.ts

packages/core/src/Node.ts

packages/core/src/NodeParser.ts

packages/core/src/Response.ts

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

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

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

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

packages/core/src/tests/Document.test.ts

packages/core/tsconfig.json