Example API changes programmatic extension defintions

[dirkbolte]

• create interfaces for different extension points
• ensure that extensions do not leak into core wiremock

References

#2553

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[tomakehurst]

I think we could possibly simplify this in most cases by defining a generic value class for this, something like:

public class ParameterisedExtensionDefinition {
    
    private final String name;
    private final Parameters parameters;

    public ParameterisedExtensionDefinition(
            @JsonProperty("name") String name,
            @JsonProperty("parameters") Parameters parameters) {
        this.name = name;
        this.parameters = parameters;
    }

    public String getName() {
        return name;
    }

    public Parameters getParameters() {
        return parameters;
    }
}

Then this could be supplied in all cases where there's an extension name + parameters required.

[dirkbolte]

@tomakehurst I updated the PR. The proposed ParameterisedExtensionDefinition is in there but created specific implementations to ensure type safety: I want to prevent that an event listener definition is registered as matcher.

I'm working on a usage thereof in the state extension. Will link to it once it's in a presentable state..