Add ::calculateDependencies() to ComponentTreeItem

This should add:

• ONLY dependencies on the config entities that 📌 "Developer-created components": mark which SDCs should be exposed in XB Active is introducing
• NOT dependencies on the module or theme that provide the SDC that the component, which is something that prior to 📌 "Developer-created components": mark which SDCs should be exposed in XB Active would've made sense

📌 "Developer-created components": mark which SDCs should be exposed in XB Active landed!

Wim Leers → credited larowlan → .

Next up: ✨ Allow specifying default props values when opting an SDC in for XB Needs work .