[BUG][php-symfony] Wrong FQCN / use import for $ref enum query parameters in DefaultApiInterface (double modelPackage prefix) #23521

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

When generating a Symfony server bundle with php-symfony, a query parameter that $refs a type: string + enum schema can produce an incorrect PHP type / use import in DefaultApiInterface.php.

Specifically, the generator appears to treat the parameter as an enum ref (isEnumRef) and the Mustache template prefixes \{{modelPackage}}\ to {{dataType}}. However, for this generator/path, dataType already resolves to a fully-qualified model type (effectively modelPackage + "\\" + shortClassName). The result is a double-prefixed / mangled class name that does not match the generated model filename / class name.

In practice this breaks static analysis and autoloading unless users add manual class_alias workarounds.

openapi-generator version

7.21.0 (openapi-generator-cli / maven artifact).
Unknown if this is a regression without bisecting; behavior is reproducible on 7.21.0.

OpenAPI declaration file content or url

Minimal reproducer:

openapi: 3.0.3
info:
  title: repro-enum-ref-query-param
  version: 1.0.0
paths:
  /items:
    get:
      operationId: listItems
      parameters:
        - $ref: '#/components/parameters/PageType'
      responses:
        '200':
          description: OK
components:
  parameters:
    PageType:
      name: pageType
      in: query
      required: false
      schema:
        $ref: '#/components/schemas/RecommendedReasonPageType'
  schemas:
    RecommendedReasonPageType:
      type: string
      enum: [home, settings]

Generation Details

Example CLI (adjust package names to your repro):

openapi-generator-cli generate \
  -i openapi.yaml \
  -g php-symfony \
  -o out \
  --additional-properties=variableNamingConvention=camelCase,phpLegacySupport=false

With a non-trivial modelPackage / namespacing setup (as in real projects), observe src/API/DefaultApiInterface.php.

Steps to reproduce

1. Save the minimal OpenAPI YAML above as openapi.yaml.
2. Run openapi-generator-cli with -g php-symfony (version 7.21.0).
3. Open the generated DefaultApiInterface.php and inspect the method signature / imports for the pageType query parameter.

Related issues/PRs

Searched open/closed issues; no exact duplicate found for “php-symfony + query $ref string enum + mangled FQCN due to modelPackage being applied twice”. Partially related discussions include enum handling for php-symfony (e.g. empty enum class issues) and general PHP namespace problems, but they do not describe this specific DefaultApiInterface / isEnumRef interaction:

• [BUG] php-symfony enum generation generates empty class #14115
• Fix enum generation for php-symfony generator #14105
• [REQ] [PHP-SYMFONY] Support BackedEnum for enum ref #16846

Suggest a fix

Align PhpSymfonyServerCodegen#getTypeDeclaration(...) output with what modules/openapi-generator/src/main/resources/php-symfony/api.mustache expects in the {{#isEnumRef}} branch:

• Either ensure dataType for enum refs is only the short class name when the template always prefixes \{{modelPackage}}\, or
• Change the template / vendor extension so that when dataType is already FQCN / already includes modelPackage, the generator does not prepend \{{modelPackage}}\ again.

Likely touch points:

• modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java (getTypeDeclaration overloads for Schema vs String)
• modules/openapi-generator/src/main/resources/php-symfony/api.mustache (isEnumRef branches for parameter typing / imports)

Actual vs expected

• Expected: DefaultApiInterface references the same PHP class as the generated enum model file, e.g. ...\Model\DTOBalanceModelRecommendedReasonPageType (name depends on naming rules), with a matching use statement.
• Actual: DefaultApiInterface may reference a non-existent stitched class name such as ...\Model\GemsAppsKuaquaOpenAPIModelDTOBalanceModelRecommendedReasonPageType (example pattern: concatenated segments resembling modelPackage + original model name), which does not correspond to the generated DTO*RecommendedReasonPageType.php file on disk.