#7258 feat: record.destroyRecord should also unload the record (@snewcomer)
#7510 feat: activate all feature flags related to CUSTOM_MODEL_CLASSES (@runspired)

#7505 Perf: Refactor PromiseManyArray and prep for RFC#745 (@runspired)
#7516 Perf: eliminate retainedManyArrayCache (@runspired)
#7454 [PERF] Class Fields Use Optimization & Made OrderedSet Faster (Again) (#7454)
#7491 relationship refactor part-1 (#7491)
#7493 Relationship Refactor (part 2): The graph should coordinate state updates (#7493)

#7651 Return inflight requests for findRecord when CUSTOM_MODEL_CLASS is on (#7651) (@igorT)
#7652 Fix for CUSTOM_MODEL_CLASS and deprecate passing non ember data records to unloadRecord and deleteRecord (#7652) (@igorT)
#7643 @ember-data/model: Simplify @cached transpilation (#7599) (@igorT)
#7554 [BUGFIX] reset previously failed linked async belongs-to now works (@sly7-7)
#7532 fix: belongsTo should not attempt load if inverse in payload provided its data (#7049) (@sly7-7)
#7550 fix: add asserts and assert tests for belongsTo/hasMany/findRecord empty responses (@runspired)
#7534 fix: #7039 Ensure meta and links update when fetched relationship is empty or does not include the data key (@sly7-7)
#7545 [BUGFIX Model] assert when 'content' is used as a property on a record (@zinyando)
#7531 fix: Closes #7053 issue preventing debug adapter removal from prod builds using the ember-data package (@sly7-7)
#7527 [BUGFIX] rollup step should deactivate ember modules polyfill >= 3.27 (@runspired)
#7425 Pass lid from relationship data to get record data (#7425)
#7448 Bugfix: coalesceFindRequests should work with non native Adapter classes (#7448)
#7463 chore: cleanup Implicit relationships (#7463)
#7453 [CHORE] burndown of InternalModel methods that can be eliminated safely (#7453)
#7226 refactor: Native Model (#7226)
#7470 chore: convert relationships to use identifiers (#7470)