[php-nextgen] Fix undefined variable $queryParams

[wuchen90]

$queryParams is used in the generated code below so this variable must exist in order to avoid undefined variable error.

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Summary by cubic

Always initialize $queryParams in php-nextgen generated API methods to eliminate “undefined variable $queryParams” when endpoints have no query params. The template now sets it by default and samples are regenerated to match.

• Bug Fixes
  • Remove the {{#hasQueryParams}} guard and unconditionally set $queryParams = []; in php-nextgen/api.mustache.
  • Regenerate samples for php-nextgen and php-nextgen-streaming (echo_api) and petstore php-nextgen so all endpoints include the $queryParams initialization.

^{Written for commit f1811a3. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 7 files

_{Re-trigger cubic}

[wuchen90]

@jebentier @dkarlovi @mandrean @jfastnacht @ybelenko @renepardon
Friendly ping for review. Thanks.

[wing328]

thanks for the PR

cc @coffeemakr @JulianVennen as well.