OpenAPI docs for project API endpoints

[tmthecoder]

OpenAPI docs for user API endpoints

Context

We want to provide user documentation for the project API Endpoints

Acceptance Criteria

• Documentation is available for all /project/ endpoints and contains appropriate parameter, precondition, and return info
• Use this guide (has a linked GitHub example): https://docs.nestjs.com/openapi/introduction

Testing

• N/A

[UZ9]

Encountered bug: creating a project with a duplicate ID results in status code 500 ALREADY_EXISTS: The resource already exists.