* Add "subtasks" type action board
* Each column will contain a work package
* The cards in the column are filtered to show only the selected work package's children
* All work packages in the project that are elligable to be a parent may be selected as a column (no milestones)
* Work packages can be dragged and dropped between parents

**Open for discussion**

* Permission handling if selected work package is located in a subproject

**Related pull request**: https://github.com/opf/openproject/pull/8504

**Notes**

* Create a new action service
* To change the parent relation: frontend/src/app/components/wp-relations/wp-relations-hierarchy/wp-relations-hierarchy.service.ts
* Column creation modal should contain a typeahead

**TODO**

* [ ] Oliver:
* [ ] Why putFromPromiseIfPristine on subtasks-action.service?
* [ ] What is subtask input for?
* [x] Upgrade account to have access to boards
* [x] Translation not shown (missing "en.js.boards.board\_type.action\_type.subtask")

**MORE INFO**
You will need two things:

1. The actual filter value for the columns, this is `parent = <selected ID for the colum>` meaning: Give me all children of &lt;selected ID&gt;
2. The applicable work packages. This will be all work packages in the current project that CAN be a parent. Which is every work package except for milestones

Begin of the insertion~~TheEnd of the insertion Begin of the deletion TheEnd of the deletion second one is a bit more complicated. You will have Begin of the insertionto~~End of the insertion Begin of the deletion toEnd of the deletion

* Begin of the insertion~~LoadEnd of the insertion Begin of the deletion LoadEnd of the deletion all Types to find out the IDs of all types which are not Begin of the insertionmilestones~~End of the insertion Begin of the deletion milestonesEnd of the deletion
* Begin of the insertion~~LoadEnd of the insertion Begin of the deletion LoadEnd of the deletion all work packages in the current project which have a type ID contained in one of the Begin of the insertionabove~~End of the insertion Begin of the deletion aboveEnd of the deletion

Begin of the insertion~~TheEnd of the insertion Begin of the deletion TheEnd of the deletion first one: Begin of the insertionInject~~ `~~TypeDmService~~` ~~andEnd of the insertion Begin of the deletion Inject `TypeDmService` andEnd of the deletion get the Begin of the insertiontypes~~ `~~typeDmService.loadAll().then(typesEnd of the insertion Begin of the deletion types `typeDmService.loadAll().then(typesEnd of the deletion => types.filter(type => Begin of the insertion!type.isMilestone))~~` ~~(thisEnd of the insertion Begin of the deletion !type.isMilestone))` (thisEnd of the deletion should be moved into a \`TypeCacheService\` but there isn&#39;t one at the momentThe second one then is rather Begin of the insertioneasy~~End of the insertion Begin of the deletion easyEnd of the deletion

Begin of the insertion~~this.halResourceService~~
~~.get(~~
~~this.pathHelper.api.v3.withOptionalProject(currentProjectId).work\_packages.toPath()~~
~~{End of the insertion Begin of the deletion this.halResourceService
        .get(
          this.pathHelper.api.v3.withOptionalProject(currentProjectId).work\_packages.toPath()
          {End of the deletion filters: buildApiV3Filter(&#39;type&#39;, &#39;=&#39;, types.map(type =&gt; type.id)).toJson() Begin of the insertion}~~
~~)~~End of the insertion Begin of the deletion }
        )End of the deletion

Begin of the insertion~~itEnd of the insertion Begin of the deletion itEnd of the deletion calls Begin of the insertiona~~ `~~GETEnd of the insertion Begin of the deletion a `GETEnd of the deletion /api/v3/projects/<current project id>/work_packages?filter=[{ type: { operator: '=', values: [1,2,3...] Begin of the insertion}]~~`End of the insertion Begin of the deletion }]`End of the deletion

Begin of the insertion~~andEnd of the insertion Begin of the deletion andEnd of the deletion this will get all work packages of the project that are eligable to be a parent - they might also already be a parent but that shouldn&#39;t Begin of the insertionmatter (editado)~~End of the insertion Begin of the deletion matter (editado)End of the deletion

Begin of the insertionFinding out all applicable parents is easyEnd of the insertion now Begin of the insertionwithEnd of the insertion the Begin of the insertion`is_milestone` filter.

now theEnd of the insertion problem is that this call might result in a large number of work packages, which is why in the Add List ... Modal we need to use this query with an autocompleter Begin of the deletion

but that could be a separate refactoring I can do laterEnd of the deletion