✨(frontend) keyboard support in sub-documents with f2 options access

adds f2 shortcut to open options menu in sub-documents

Signed-off-by: Cyril <c.gromoff@gmail.com>

✨(frontend) adds f2 shortcut using a fakenode since it's outside the treeview

Signed-off-by: Cyril <c.gromoff@gmail.com>

✨(frontend) add sr-only instructions with aria-describedby links

improves screen reader support with contextual accessibility guidance

Signed-off-by: Cyril <c.gromoff@gmail.com>

✅(frontend) add e2e test to check focus behavior with F2 shortcut

ensures F2 correctly focuses the expected UI element

Signed-off-by: Cyril <c.gromoff@gmail.com>

CHANGELOG.md

@@ -18,6 +18,8 @@ and this project adheres to
 - 🛂(backend) stop throttling collaboration servers #1730
 - 🚸(backend) use unaccented full name for user search #1637
 - 🌐(backend) internationalize demo #1644
+- ♿(frontend) improve accessibility:
+  - ♿️Improve keyboard accessibility for the document tree #1681
 
 ### Fixed