Update ICommentsManager with reaction methods

Fix psalm errors
Reorder methods and remove return null
Use best pattern on docblock

Goals: update https://github.com/ChristophWurst/nextcloud_composer/ with reaction methods.
The script
https://github.com/ChristophWurst/nextcloud_composer/blob/master/build.sh


only get lib/public classes

Signed-off-by: Vitor Mattos <vitor@php.rio>