add internals file and use it to organize imports

src/index.js

@@ -1,24 +1,30 @@
 
-export { Y } from './utils/Y.js'
-// export { UndoManager } from './utils/UndoManager.js'
-export { Transaction } from './utils/Transaction.js'
-export { ItemJSON } from './structs/ItemJSON.js'
-export { ItemString } from './structs/ItemString.js'
-export { ItemFormat } from './structs/ItemFormat.js'
-export { ItemEmbed } from './structs/ItemEmbed.js'
-export { ItemBinary } from './structs/ItemBinary.js'
-export { GC } from './structs/GC.js'
-
-export { YArray as Array } from './types/YArray.js'
-export { YMap as Map } from './types/YMap.js'
-export { YText as Text } from './types/YText.js'
-export { YXmlText as XmlText } from './types/YXmlText.js'
-export { YXmlHook as XmlHook } from './types/YXmlHook.js'
-export { YXmlElement as XmlElement, YXmlFragment as XmlFragment } from './types/YXmlElement.js'
-
-export { createRelativePosition, createRelativePositionByOffset, createAbsolutePosition, compareRelativePositions, writeRelativePosition, readRelativePosition, AbsolutePosition, RelativePosition } from './utils/relativePosition.js'
-export { ID, createID, compareIDs } from './utils/ID.js'
-export { isParentOf } from './utils/isParentOf.js'
-
-export { writeStructs, writeStructsFromTransaction, readStructs } from './utils/structEncoding.js'
-export { getState, getStates, readStatesAsMap, writeStates } from './utils/StructStore.js'
+export {
+  Y,
+  Transaction,
+  YArray as Array,
+  YMap as Map,
+  YText as Text,
+  YXmlText as XmlText,
+  YXmlHook as XmlHook,
+  YXmlElement as XmlElement,
+  YXmlFragment as XmlFragment,
+  createRelativePosition,
+  createRelativePositionByOffset,
+  createAbsolutePosition,
+  compareRelativePositions,
+  writeRelativePosition,
+  readRelativePosition,
+  AbsolutePosition,
+  RelativePosition,
+  ID,
+  createID,
+  compareIDs,
+  writeStructs,
+  writeStructsFromTransaction,
+  readStructs,
+  getState,
+  getStates,
+  readStatesAsMap,
+  writeStates
+} from './internals.js'