test(#758): cover @JsonIgnoreProperties(ignoreUnknown) across bundles

[jbonofre]

Refs #758 (does not close it: the issue is not reproduced yet).

Summary

Extends the camel-jackson Pax Exam test so that the Jackson unmarshal runs against an entity that:

• is annotated with @JsonIgnoreProperties(ignoreUnknown = true), and
• lives in its own bundle, separate from jackson-databind.

The input JSON carries a property the entity does not declare. If Jackson stops honouring the annotation across the bundle boundary, the unmarshal fails and the mock endpoint receives nothing, so the test fails.

Investigation

• The camel-jackson bundle's Jackson Import-Package ranges are identical in 4.18.2 and 4.18.4.
• The jackson feature only moves databind and core from 2.21.2 to 2.21.4; jackson-annotations is unchanged.
• The only upstream Camel change is CAMEL-23786 (JsonMapper with BLOCK_UNSAFE_POLYMORPHIC_BASE_TYPES), which does not affect unknown-property handling. A plain-Java check on Jackson 2.21.4 confirmed this.
• This test passes on the current tree (4.22.1-SNAPSHOT) and fails when the annotation is removed, so it can detect the problem. It was not run against the 4.18.4 tag.

The reporter's environment (duplicate or stale jackson-annotations bundles) remains the most likely cause.

Test plan

• mvn -o verify -pl tests/features/camel-jackson passes
• Same run fails (Expected: <1> but was: <0>) with the annotation removed

AI-assisted, on behalf of JB Onofré.