feat: add solver job start event

[zepfred]

This pull request adds a new job configuration that allows an action to be run when the solver starts the solving process. The current approach uses a PhaseLifecycleListenerAdapter to trigger the event because the API SolverEventListener would need to be changed in order to add a new solver event.

[triceo]

We've already added events before, haven't we? The solution initialization event comes to mind.
What makes this one different, why are we suddenly afraid of changing the API for it?

[zepfred]

We've already added events before, haven't we? The solution initialization event comes to mind.

We used the PhaseLifecycleListenerAdapter for this specific event, which was the appropriate choice as it relates to the phase itself.

What makes this one different, why are we suddenly afraid of changing the API for it?

In this case, it is a solver event and should be called once during DefaultSolver#solvingStarted, but it can also be solved using the phase event lifecycle as proposed by this PR. My goal was to keep this pull request simple because changing the contract SolverEventListener would impact many other areas of the solver.

We may consider creating a separate issue to refactor SolverEventListener to make the solver events system more extensible.

[triceo]

Looks good so far.

[triceo]

Please switch to listen to the proper event. After that, LGTM.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
95.5% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud