Workflow run retention policy

[thomasjiangcy]

Desired Behavior

It will be nice to have a way to configure retention period and automatically clean up workflows in terminal states without manual intervention, similar to Temporal's History Scavenger.

Possible design

// openworkflow.config.ts

export default defineConfig({
  ...,
  retention: {
    enabled: true,
    period: "30d", // shorthand, any workflow runs in terminal state past 30 days will be removed
  }
});

This is to keep it simple for now. In the future there could be more fine-grained control - e.g. frequency of this job, when to run it, customize what workflow run statuses to clean up.

I think there's a dependency on #246 before this can be considered.

[jamescmartinez]

great request, I want this too.

you're right that this depends on #246 - once we have built-in recurring scheduling (soon), retention can run as an internal scheduled job instead of needing external triggers.