[BUG] Description

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

When I run openapi-generator-cli the Models and containing files are being output with their names containing the full namespace of the API classes. This is very awkward to read. I'd like the output to contain only the Model name, without the namespace.

E.g for class

namespace My.NameSpace.Common.V1.Models.Dto
{
    public partial class PortfolioAsset
    {
        // properties

The output looks like

my-namespace-common-v1-models-dto-portfolio-asset.ts

With the content of the file as

export interface MyNamespaceCommonV1ModelsDtoPortfolioAsset { 
    // parameters
}

I just want the file to be called portfolio-asset.ts and the content to be

export interface PortfolioAsset { 
    // parameters
}

How can I do this?

##### openapi-generator version

5.2.1

##### OpenAPI declaration file content or url

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Generation Details

Steps to reproduce

Related issues/PRs

Suggest a fix

Start by reproducing the report with openapi-generator-cli 5.2.1 using the C# namespace example and inspect the generated model filenames and TypeScript declarations. The issue does not name a source file or test, so trace the model naming path first. Done means generated files use the model name only, such as portfolio-asset.ts, and the declaration is PortfolioAsset.