[ENH] About the Elsa.Workflows.Pipelines.ActivityExecution

[zfchai]

Suggest aligning the ActiveExecution programming paradigm with the WorkflowExecution, for example:

• ActiveExecutionPipeBuilder suggests renaming it to ActiveExecutionPipeBuilder
• Add the ActiveExecutionMiddleware class with the following code:

namespace Elsa.Workflows.Pipelines.ActivityExecution;

public abstract class ActivityExecutionMiddleware : IActivityExecutionMiddleware
{
    protected ActivityExecutionMiddleware(ActivityMiddlewareDelegate next) => Next = next;
    protected ActivityMiddlewareDelegate Next { get; }
    public abstract ValueTask InvokeAsync(ActivityExecutionContext context);
}

[sfmskywalker]

Makes sense. Do you want to submit a PR?