Fix normalization to prevent unnecessary allOf wrapping for oneOf and anyOf

[lucy66hw]

Implement context-aware normalization with isInComposition flag to skip normalization for oneOf/anyOf items.
#22578

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[lucy66hw]

@wing328 Could you please review?

[wing328]

@lucy66hw thanks for the PR

here is how i look at the issue. ideally the following should be handled without any issue (in any usage), right?

Pet:
  oneOf:
    - allOf:  
        - $ref: '#/components/schemas/Dog'
      title: dog
      description: "A dog pet"
    - allOf:  
        - $ref: '#/components/schemas/Cat'
      title: cat
      description: "A cat pet"
    - allOf:  
        - $ref: '#/components/schemas/Bird'
      title: bird
      description: "A bird pet"
  discriminator:
    propertyName: petType

i think your PR is more like a workaround/patch to address a particular use case.

the above use of allOf can be handled properly (e.g. as a property in model) but not everywhere (e.g. sub-schema in oneOf), which is definitely something I think we should address.

[lucy66hw]

@wing328 Thanks. Just to clarify—are you suggesting we should make the generator resolution handle allOf([$ref]) even when it appears as a oneOf sub-schema, rather than changing it in the normalizer?

[wing328]

my understanding is that we don't need this any more.

happy to reopen if needed