Fix missing imports for schemaMapping in API interfaces

[SubhamAshok]

Fixes #24232

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[cubic-dev-ai]

All reported issues were addressed across 21 files

<sub>Reply with feedback, questions, or to request a fix.

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[cubic-dev-ai]

All reported issues were addressed across 1 file (changes from recent commits).

<sub>Tip: Review your code locally with the cubic CLI to iterate faster.

Re-trigger cubic</sub>

[SubhamAshok]

cc @wing328 @jpfinne - I saw PR #24261 was stalled. I tried a different approach here that seems to pass CI without triggering those extra imports. Let me know what you think.

[wing328]

cc @OpenAPITools/generator-core-team as the change covers default codegen

[cubic-dev-ai]

No issues found across 3 files

_{Re-trigger cubic}

[jpfinne]

@SubhamAshok you handle the missing imports for the response.
My PR #24261 add the imports for the parameters.

I guess we need both

[jpfinne]

I find the generatedContract method simpler to review:

Map<String, File> files = generateFromContract(
                "src/test/resources/3_0/spring/issue_24232.yaml", SPRING_BOOT,
                Map.of(USE_SPRING_BOOT4, true),
                codegenConfigurator ->
                        codegenConfigurator
                                .addTypeMapping("string+custom", "MyCustomId")
                                .addSchemaMapping("MyKey", "MyCustomKey")
                                .addImportMapping("MyCustomId", "org.myorg.MyCustomId")
                                .addImportMapping("MyCustomKey", "org.myorg.MyCustomKey"));