Category selection: Expose all category fields to Twig template

[FlxRobole]

Problem description

I encounter this issue is at the threshold of Bug/Feature.

Context: Our company is working on a list view that can be filtered from within the frontend. Filterable list items can be added via a block, each block item having a "category_selection" field. A dump of the item's category looks like the following in Twig:

array:11 [▼
  "id" => 9
  "key" => "privatperson"
  "name" => "Privatperson"
  "description" => null
  "meta" => []
  "keywords" => []
  "defaultLocale" => "de"
  "creator" => "Adam Ministrator"
  "changer" => "Adam Ministrator"
  "created" => DateTime @1712736941 {#4987 ▶}
  "changed" => DateTime @1712736941 {#4986 ▶}
]

Now, compare this to an item returned via sulu_categories():

array:15 [▼
  "locale" => "de"
  "id" => 10
  "key" => "unternehmen"
  "defaultLocale" => "de"
  "name" => "Unternehmen"
  "description" => null
  "medias" => array:1 [▶]
  "ghostLocale" => "de"
  "meta" => []
  "creator" => "Adam Ministrator"
  "changer" => "Adam Ministrator"
  "created" => "2024-04-10T08:15:51"
  "changed" => "2024-04-10T08:15:51"
  "children" => []
  "parentId" => 7
]

Problem: Categories exposed by category_selection content type miss some field (e.g. ghostLocale, medias and most importantly parentId which we require to filter items in the frontend). There is no Twig function to resolve a full category (e.g., sulu_category_load) and no properties parameter as for e.g. smart_content to explicitly define the fields that should be resolved

Proposed solution

Depending on what fits best to the Sulu flavor of configuring content-types, either

1. Always expose all fields/values of a category to the Twig template so that it is identical with the items returned by sulu_categories()
2. OR add a properties collection-type parameter to category_selection
3. OR add a Twig function sulu_category_load to CategoriesBundle