[BUG][typescript] Array items are incorrectly marked as nullable

Description

Under some very specific conditions, | null is added to array item type when it shouldn't be there.

openapi-generator version

7.22.0

OpenAPI declaration file content or url

{
    "info": {
        "description": "Test",
        "title": "test",
        "version": "1.0"
    },
    "openapi": "3.1.0",
    "servers": [
        {
            "url": "http://localhost:5000"
        }
    ],
    "components": {
        "schemas": {
            "Response": {
                "title": "Response",
                "type": "object",
                "properties": {
                    "nullable": {
                        "type": "array",
                        "default": null,
                        "items": {
                            "anyOf": [
                                {
                                    "type": "string"
                                },
                                {
                                    "type": "null"
                                }
                            ]
                        }
                    }
                },
                "required": [
                    "nullable"
                ]
            },
            "ResponseGet": {
                "title": "ResponseGet",
                "type": "object",
                "properties": {
                    "nonNullable": {
                        "type": "array",
                        "default": null,
                        "items": {
                            "type": "string"
                        }
                    }
                },
                "required": [
                    "nonNullable"
                ]
            }
        }
    },
    "paths": {
        "/api": {
            "get": {
                "responses": {
                    "200": {
                        "content": {
                            "application/json": {
                                "schema": {
                                    "$ref": "#/components/schemas/ResponseGet"
                                }
                            }
                        },
                        "description": "OK"
                    }
                }
            }
        }
    }
}

Generation Details

{
    "generatorName": "typescript"
}

Steps to reproduce

When generating code for the above API spec, the Response class should have 'nullable': Array<string | null>; and the ResponseGet class should have 'nonNullable': Array<string>;. Instead, both receive Array<string | null>;. I'm unable to determine the exact cause; for example, changing "#/components/schemas/ResponseGet" -> "#/components/schemas/Response" causes both models to be generated correctly. Removing "default": null also seems to somehow fix the bug.

Start by generating the TypeScript client from the supplied OpenAPI declaration and compare the generated Response and ResponseGet model properties. Trace how the TypeScript generator combines array item schemas with default nullability, then add or update a regression test for this specification. Done means nullable uses Array<string | null> while nonNullable uses Array.