Add event for hooks after database operations have been done

[PhMemmel]

In some cases you want to react to events fired by tool_lifecycle after the corresponding database actions have been performed, so you can read from the database again to have a consistent database state.

This PR adds such an event.

[NinaHerrmann]

Hello sorry for the late reply!
Could you elaborate in which use case you want to use this?
Cheers, Nina

[PhMemmel]

Hi @NinaHerrmann,
thank you for the reply!

I have implemented an alert block which is shown on the dashboard to the users to inform them that they have courses to handle. This block tracks, calculates and updates all currently available interactive steps and shows a message like "You have 4 courses requiring your attention, please click here to handle them." including a link leading to the tool_lifecycle view page. This block only shows if there are courses to handle.

Therefore I need a hook at the exact point where the current process/step has already finished, so the database queries return the correct state.

[NinaHerrmann]

Uh nice context I see the application for that!
Do you mind linking the block in the documentation if we do an additional subsection? :)
We try to review as fast as possible! :)

[PhMemmel]

The block is currently closed source and it also requires my other contribution (#143). If it is of public interest, let me know, I will try to figure out, if it is possible to release the source code publicly.