[Feature] Filter out Accounts without Active Subscriptions

### Is there an existing feature request for this?

- [X] I have searched the existing issues

### Describe the Feature

Currently the `recurly__account_overview` and `recurly__account_daily_overview` end models include **all** accounts within the Recurly implementation. However, it has come to our attention that a number of Recurly customers only care about the accounts with a subscription, which is ~1/4 of the entire account population. This is likely a common pattern with companies with a free-tier plan.

As such, a proposed feature would be to add a filter to the above mentioned models that filter out any accounts that are not tied to an active subscription. In order to do this, we will need to apply a join between the `account_history` and the `subscription_history` models before rolling up into the final end models to then filter out any non-matches. This would likely be best fascilitated within an intermediate model that could possibly have a `recurly__using_active_accounts` (or something of the sort) variable that will allow users to leverage the filter or the default behavior of the package.

### Describe alternatives you've considered

No alternatives at the moment. Customers may apply the join and filter after the package has run, but this still requires the models to run and incur costs they otherwise would wish to not have to take on.

### Are you interested in contributing this feature?

- [ ] Yes.
- [ ] Yes, but I will need assistance and will schedule time during your [office hours](https://calendly.com/fivetran-solutions-team/fivetran-solutions-team-office-hours) for guidance.
- [ ] No.

### Anything else?

This was originally raised within Issue #

Start with the recurly__account_overview and recurly__account_daily_overview models, then inspect account_history and subscription_history to understand the available account and subscription records. Define how an active-account filter and its configurable default should work, and verify that the final models exclude accounts without active subscriptions while preserving the existing behavior when disabled.

Written by the indexing model from the issue text.