[Java][Spring] useRecords: no @NotNull on records without bean validation

[Sekator778]

#25131 removed @NotNull and its import from classes when useBeanValidation is off. The record template from #25200 still printed the annotation, so with useRecords and useBeanValidation=false a record with a required property stopped compiling. Records now follow classes there. With bean validation on, or useRecords off, the output is unchanged.

@cachescrubber @welshm @MelleD @atextor @manedev79 @javisst @borsch @banlevente @Zomzog @martin-mfg @KannaKim

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Summary by cubic

Fixes the Java Spring record template emitting @NotNull on required fields when useBeanValidation is off, which produced records that did not compile because the annotation import was missing. Records now match the classes behavior and emit no bean validation annotations when validation is disabled. Output is unchanged when bean validation is on or useRecords is off.

Adds regression tests covering record generation with and without bean validation.

^{Written for commit db7cd1e. Summary will update on new commits.}

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