chore: drop summary elements, do not auto-select first item
- Dropped the use of summary elements in favor uls and v-ifs.
- Do not automatically select the first child item when clicking on a parent.
- Kept the behavior where only one menu section can be expanded at a time.
- Improved navbar's accessibility by leveraing
role
andaria-
attributes.
Closes #921 (closed), #923 (closed)
Edited by Paul Gascou-Vaillancourt