[1747] Automatically select more newly created elements

[pcdavid]

This is a draft for the moment. It works but:

• it requires Sirius Web 2025.12.2 (not yet released) with Register Let-defined variables into OperationEvaluationResult.newInstances eclipse-sirius/sirius-web#5955
• it is missing the corresponding tests
• we might want to apply the enhancement to more tools (or merge as is and generalize later)

Bug: #1747
Signed-off-by: Pierre-Charles David pierre-charles.david@obeo.fr

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