Unify integration-tests environment

[davelsio]

Description

Currently, integration tests for both graphql-server-model-codegen and single-page-app-codegen create independent Zendro environments, each implementing its own command-line interface.

Regardless of the tests themselves, when the API specification changes, both code-bases have to be updated simultaneously, leading to code duplication and independent environment evolution.

Proposals

1. Create a unified tool that can be used to dynamically set up the development environments required for each repository.

2. Consider moving the integration test-suites for both code generators to a separate platform that uses this tool to set up the desired environment.

Features

The tool should include the following features:

• Create a dynamic Zendro environment with multiple graphql-server and single-page-instances via a configuration file.
• This environment should be fully detachable (i.e. independent from any of the code-generator projects).
• Provide a command-line interface to control the environment creation process at various points, including installation of services, run code-generators, apply patches, and manage a docker-compose configuration.
• Integrate test runner functionality (e.g. mocha) via the command-line interface, providing shortcut options to run useful environment commands (e.g. -r to restart docker containers or -g to re-generate code).