v0.9.0 — view-scoped chunk positions Additive (minor): adds parent_chunk_type + parent_chunk_id to UpdateChunkPositionRequest and GetChunkPositionsRequest so chunk positions are scoped per view (view = the parent chunk navigated into; root view = CHUNK_TYPE_UNSPECIFIED + empty id). A read returns only the requested view's positions. Optional chunk_type filter retained (applies within the view). No breaking changes. Merged via !16 (register-view-scoped-positions).