[JAVA] [SPRING] [PKMST] [MICRONAUT] XML wireformat: Fix Jackson useWrapping=false, JAXB+Jackson namespaces

[Philzen]

Closes #2417 Closes #3223 Closes #5078 Closes #18869

Replaces #18392

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[Philzen]

Hey @chschu! Sorry for this being held up for so long... i've now finally got around to open this PR.

Following our discussions, could you briefly review this and see if you have anything to add? Would be looking forward to your feedback, and otherwise these fixes finally hitting the 7.7 release :)

[Philzen]

@wing328 if you have some time at the weekend i'd highly appreciate this PR going into v7.7 if possible.

I haven't heard back from @chschu which is co-author of this fix (which actually kickstarted my contributions here as it pointed me into the right direction), but from our discussion over at #18392 they seemed already pretty satisfied at the time.

[wing328]

thanks for the PR, which has been merged.

[martin-mfg]

Hi @Philzen, it seems this PR broke the java-camel samples.

openapi-generator\samples\server\petstore\java-camel> mvn clean verify

results in several failed tests.

Coud you have a look at this?