[BUG] [C++][Pistache] requestBody application/json schema "type: boolean" generates type mismatch

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• 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

If requestBody is specified as application/json type boolean, code similar to the following is generated...and request.body() can not be coerced into boolean without parse(...).get_to().

void DefaultApi::pet_post_handler(const Pistache::Rest::Request &request, Pistache::Http::ResponseWriter response) {
    try {


    // Getting the body param
    
    bool body;
    
    try {
        body = request.body();

openapi-generator version

7.10.0...but have seen similar in many versions since 4.1.0

OpenAPI declaration file content or url

openapi: 3.0.3
info:
  title: Swagger Petstore - OpenAPI 3.0
  version: 1.0.11
paths:
  /pet:
    post:
      requestBody:
        content:
          application/json:
            schema:
              type: boolean
        required: true
      responses:
        '200':
          description: Successful operation
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Pet'          
            application/xml:
              schema:
                $ref: '#/components/schemas/Pet'
components:
  schemas:
    Pet:
      required:
        - name
      type: object
      properties:
        name:
          type: string
          example: doggie

Generation Details

Steps to reproduce

java -jar Downloads/openapi-generator-cli-7.10.0.jar generate -i dog.yaml -g cpp-pistache-server -o exp

Related issues/PRs

Appears to be caused by https://github.com/OpenAPITools/openapi-generator/pull/3509/files

Suggest a fix

Generate code similar to what 4.0.2 generates:

void DefaultApi::pet_post_handler(const Pistache::Rest::Request &request, Pistache::Http::ResponseWriter response) {

    // Getting the body param
    
    bool body;
    
    try {
      nlohmann::json::parse(request.body()).get_to(body);
      this->pet_post(body, response);

Reproduce the issue with the provided OpenAPI declaration and the cpp-pistache-server generation command, then inspect the generated pet_post_handler body handling. Compare the current output with the 4.0.2 example; done when a boolean application/json request body is parsed as JSON before being passed to pet_post.