entity-metadata | Basic metadata on entities such as people corporations | Dataset library

After reading and trying everything so far to update my additionalCollectionStates to my EntityCollection (based on the few infos from the docs, this SO Question, this other SO Question, another SO question and an issue from the github repository) I find myself stuck with what should be a fairly common task to do and was no problem at all before using ngrx: sorting of a stored collection of entities with ngrx. Searching for solutions takes me back to the same 10 links I have already seen 5 times and most examples are either too basic or outdated or don't use ngrx/data at all or similar questions don't have answers at all.

Environment: Angular 9.1.7, ngrx 9.1.2, macOS 10.14.6

Goal

Add and update own additionalCollectionState to my EntityCollection as described in the docs for sorting and pagination. I do not get the sortQuery Properties (sortField, sortDirection) from the server but rather set it in my GUI and sort the collection based on them. I know there exists the sortComparer setting on EntityMetadataMap but it's not flexible enough for my means, I want to dynamically sort the collections in different MatTables across the app. This additional property should be updated, whenever the sort order / field in a MatTable changes.

What I have achieved so far:

The ngrx/data way of additionalCollectionState as desribed above works, my collection is initialized with the data I provided in the EntityMetadataMap. Updating the custom collection properties however does not work in the way it is understood by me from the docs. Since I don't get the sortQuery property from the server, the ResultsHandler is not called.

I approached this problem in two ways: a) using ngrx & ngrx/entity Methods and b) the ngrx/data way by trying to extend a custom EntityCollectionReducer

a) I was successful in creating a custom Action and custom Reducer and updating a state property but not the previously defined collection property. My action is basically:

I have a standard setup from the NGRX data docs with one Entity. Everything works with JIT but when I do AOT then I get following Error:

I am having a bit of difficulty with @ngrx/data and am hoping one of you Geniuses out there can help me out.

I have an entity collection and would like to store some additional information to reduce round trips to the server and also reduce redundant loading. I have a table of data and only want to load one page at at time into the entity collection, in order to be able to do this I would like to add additional meta data to my collection so that I know when to load more data. E.g. when I reach the end of the loaded data load more (pagination would need to know how many records exist and how many have been loaded).

According to the documentation I can add additionalCollectionState but need some way of updating the new state properties.

I figured I would copy/paste the example code that they have as a base and modify it to reflect my own properties.. the problem is that I immediately get a typescript error on the =>Action

Generic type 'Action' requires 1 type argument(s)