[Engine.Analyze] ClusteringEngine: set correct values in load()

[fredroy]

Trying to implement strict type for setValue() and stumbled on ClusteringEngine which was setting wrong values (copy-paste I suppose)

+ fix other strict type usages

---

By submitting this pull request, I acknowledge that
I have read, understand, and agree SOFA Developer Certificate of Origin (DCO).

---

Reviewers will merge this pull-request only if

• it builds with SUCCESS for all platforms on the CI.
• it does not generate new warnings.
• it does not generate new unit test failures.
• it does not generate new scene test failures.
• it does not break API compatibility.
• it is more than 1 week old (or has fast-merge label).

[fredroy]

[ci-build][with-all-tests]