redesign concept details page

**⚠ work in progress, not yet ready to merge**

this provides a more compact UI for concept details while introducing view models

the UI is based around a summary at the top, with further details categorized by language - as such it is a significant departure from earlier UIs primarily based on internal data models


To Do
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* [x] labels
* [ ] relations
* [x] collections
* [x] notes
* [ ] notations
* [ ] matches
* [ ] remove dead code
* [ ] styling

once this is done, we should integrate extend the concept hierarchy to load concept details into a pane next to the tree