Stop emailing refunded WooCommerce customers as if nothing happened

**Objective:** Find customers refunded in WooCommerce in the last `{lookback-days}` days (default 14) who are still receiving Drip campaigns, and tag them with `{tag}` in Drip if a tag is given and the user confirms.

**Step 1: List recent refunds**

Call `woocommerce-get-refund` with `created-date.from` set to today minus `{lookback-days}` days and `max-records` set to 200. Group by customer email: refund count, total refunded per currency, reasons, and the order numbers.

**Step 2: Check each refunded customer in Drip**

For each email, call `drip-get-subscriber` with `email` set to it, and `drip-get-campaign-subscriber` with the same `email`. Note their Drip status, tags and every campaign whose campaign status is active.

**Step 3: Report**

List refunded customers who are active Drip subscribers and still in at least one active campaign: email, total refunded, reasons, and the campaigns. Then give counts for refunded customers who are unsubscribed, not in Drip, or in no active campaign.

**Step 4: Tag (only if a tag was given)**

If `{tag}` is blank, stop after the report. Otherwise show who would be tagged and ask the user to confirm. On a clear yes, call `drip-add-subscriber-tag` once per confirmed active subscriber with `email` and `tag` set to `{tag}`, skipping anyone who already has it, then report tagged, failed and skipped.

**Rules & Guidelines:**

* Tools whose names start with drip- are on the drip server; tools whose names start with woocommerce- are on the woocommerce server. Both servers must be connected.
* Match people across the two systems by email, compared case-insensitively with surrounding spaces removed. Drip uses `email`; WooCommerce uses `email` on customers and `customer-email` on orders, order lines and refunds.
* Compute dates as today minus the stated number of days and pass them as YYYY-MM-DD.
* The only write allowed is `drip-add-subscriber-tag`, for active Drip subscribers only, after the user confirms in Step 4, and only when `{tag}` is given.
* Do not remove anyone from a campaign or unsubscribe them. Do not call `drip-remove-subscriber-from-campaign`, `drip-remove-subscriber-from-all-campaigns` or `drip-unsubscribe-subscriber`; recommend them in the report if they fit, and leave the decision to the user.
* Never tag emails that are not in Drip; tagging an unknown email creates a new subscriber.
* Make no changes in WooCommerce. Do not call `woocommerce-add-customer`, `woocommerce-update-customer`, `woocommerce-update-order`, `woocommerce-add-order-note`, `woocommerce-add-coupon` or `woocommerce-add-refund`.

**Validation:**

* If there were no refunds in the period, say so and stop.
* A refund with a blank customer email is a guest order; count it and leave it out.
* Never add amounts in different currencies together; total each currency separately.