[php-nextgen] Remove invalid @implements ArrayAccess tag in models with parents

[JulianVennen]

This comment is currently invalid on classes with parent models as the import is missing. Since the parent already has this comment, I decided to just remove it here.

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Summary by cubic

Removed the invalid @implements ArrayAccess docblock from generated PHP php-nextgen models that extend a parent. This prevents duplicate/incorrect annotations and fixes static analysis/IDE warnings.

• Bug Fixes
  • Emit @implements ArrayAccess<string, mixed> only for models without a parent (guarded with {{^parentSchema}} in model.mustache).
  • Regenerated PHP samples to remove the tag from child classes (e.g., Cat, Dog, DataQuery).

^{Written for commit 753250b. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 7 files