[Ember Data 4.7] Models disappear when more than 2400 instances

[mkszepp]

Description

While creating the example repository for a other bug (#8262) i have deteced this bug (which is present in the repository https://github.com/mkszepp/ember-stable-identifier)
When i have 2400 models in store and add model n. 2401, other models will be lost.
After removing a model all other models return.
When i readd model n. 2401, the .length returns a wrong number of models.
This problem is not present in ember 4.4 with ember data 4.4.

Versions

Ember Js: 4.7.0+
Ember Data: 4.7.3
Test on Browser: latest Chrome + Firefox

[runspired]

do you have a reproduction for this? or just a list of steps?

the only thing that stands out here as intriguing is that 2400 is exactly twice the size of our slice increment when we copy from source-array to proxied-array.

[runspired]

Found bug, have fix