GLSP-1423 Add MovementBehavior to control invalid multi element movements

[ivy-lli]

What it does

Fixes: eclipse-glsp/glsp#1423

Per default change the behavior that all selected elements will be reset to it's origin location when one move is invalid. But add an IMovementBehavior type where this can be changed to the old style.

Question:

• Should also the red border feedback be on both elements?
• Better name for the options type / flag on the type?

How to test

Add to the examples/workflow-standalone/src/di.config.ts

export default function createContainer(options: IDiagramOptions): Container {
  ...
  container.bind(TYPES.IMovementRestrictor).to(NoOverlapMovementRestrictor);
  container.bind(TYPES.IMovementBehavior).toConstantValue({ allElementsNeedToBeValid: true }); //or false for the old behavior
  return container;
}

New behavior:

Old behavior:

Changelog

• This PR should be mentioned in the changelog
• This PR introduces a breaking change (if yes, provide more details below for the changelog and the migration guide)

[martin-fleck-at]

I tested this change and everything works as expected, thank you very much, Lukas! I just have a few minor comments and then we can merge this PR in my opinion.

• Should also the red border feedback be on both elements?
  Good question! I can see arguments for both sides as you may not know which move is the culprit if all elements get the erroneous feedback. So I think leaving it only on the actual invalid move for now is fine.

• Better name for the options type / flag on the type?
  (see inline comment)

[martin-fleck-at]

I'm a little bit on the fence about whether it should be called IMovementBehavior (as we have with the IMarqueeBehavior) or IMovementOptions (as we have with the IHelperLineOptions). I think both are probably fine, just wanted to note that down somewhere. We should probably unify that at some point.

[ivy-lli]

I named it indeed after the MarqueeBehavior (as I invented this too 🙈), however, I think I like Options more, so I will call it options.

[martin-fleck-at]

Great, thank you very much for the quick turnaround! LGTM!