Remove Merge-Tree and SharedString ISegment Deprecations

[anthony-murphy]

---

"@fluidframework/merge-tree": minor
"@fluidframework/sequence": minor

---

"section": deprecation

The current ISegment interface over-exposes a number of properties which do not have an external use case, and any external usage could result in damage to the underlying merge-tree including data corruption.

The only use case that will continue to be supported is determining if a segment is removed. For this purpose we've added the free function segmentIsRemoved(segment: ISegment): boolean.

For example, checking if a segment is not removed would change as follows:

- if(segment.removedSeq === undefined){
+ if(!segmentIsRemoved(segment)){

The following properties will be removed on ISegment and its implementations:

• clientId
• index
• localMovedSeq
• localRefs
• localRemovedSeq
• localSeq
• movedClientsIds
• movedSeq
• movedSeqs
• ordinal
• removedClientIds
• removedSeq
• seq
• wasMovedOnInsert

Additionally, the following types will be remove, and will become internal (i.e. users of the Fluid Framework will not have access to them):

• IMergeNodeCommon
• IMoveInfo
• IRemovalInfo
• LocalReferenceCollection

[anthony-murphy]

#23323