Store the hide-resolved filter in user storage and restore it when
entering the workspace or viewer, consistent with canvas comment
visibility from #10239. Match the comments filter separator styling to
the main menu and add the missing mentions option in the viewer
dropdown.
Closes#10686
Signed-off-by: Andres Gonzalez <andres.gonzalez79@gmail.com>
Co-authored-by: Cursor <cursoragent@cursor.com>