WIP: Demonstrate Hierarchy Functions

[etimr]

Provides an example of an hierarchy function as ListReport and ValueHelp

• currently only READ
• only on HANA

Changes:

• LineItem parent.name is removed from app/common.cds, because it leads to OData requests with $expand for an hierarchy function which are not supported yet
• sap.common.CodeList aspect was removed from Genres entity because it provides ValueHelp dialog implicitly through annotation @cds.odata.valuelist. It also uses the annotation @cds.autoexpose, because of this entity Genres should be exposed explicitly in CatalogService and ReviewService after sap.common.CodeList is removed.
• renaming in the view GenreHierarchy is temporal and will be solved by CAP Java team in the future

node   as node_id,
parent_node as parent_id

• to enable tree tables as ListReport add to manifest.json:

"tableSettings": {
     "type": "TreeTable",
     "hierarchyQualifier": "NodesHierarchy",
   ...
}

• to enable tree table for ValueHelp hierarchical entity should be annotated with PresentationVariant and root entity with PresentationVariantQualifier

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[agoerler]

why do we add the node element?

[etimr]

I need an additional field for the association:
Association to one Genres on parent.node = parent_node;
as we discussed, following doesn't work yet:
Association to one Genres on parent.ID = parent_node;

[agoerler]

we can get rid of the parent_node FK element with @eugene-andreev 's upcoming change.

[agoerler]

the information in the ID and node column is redundant

[etimr]

yes, because I can't use the key ID in the association -> will be removed with the change of @eugene-andreev

[agoerler]

we need to check if we need this annotation if we don't rename anything

[etimr]

I agree, it looks the same in the example I got from Gwendal (no renaming), but I can't find confirmation in the documentation -> ask UI colleagues