Account subsidiary nodes for node filter

[CatoLeanTruetschel]

User story

1. As a quality manager
2. I want / need to adjust the number of nodes shown in my shortest path visualization
3. So that I can modify visualizations to make it understandable for my manager

Acceptance criteria

• Affects Sliderfunction for number of nodes Sliderfunction for nodes & edges #134
• Subsidiary nodes included in calculation of nodes to be shown
• Visualization changes when slider function is used

Definition of done

• Documentation conform with tsdoc
• Reviewed with 4 eyes principle
• Did not break other code
• Understandable documentation for developers

Developers Explanation:
The node filter limit is mostly useless, as it does not account for subsidiary nodes. It does not matter what limit is set, the nodes that are to be removed as per the limit, become subsidiary nodes, such that the edges can still be displayed. The total number of displayes nodes is not changed, rendering the limit mostly useless.
A possible solution is to include subsidiary nodes into the limit. There is still the question open, which nodes are to be removed if the total number of nodes exceed the set limit of nodes. If we remove random nodes, the query result will not be stable between subsequent queries, which can in the worst case lead to flickering of nodes when queries are executed in small periods of time. A possible solution here, is sorting by some stable order (for example by id) and removing the first (last) nodes in this sort-order.

[CatoLeanTruetschel]

/CC @julevdl @zuberman35