Move a Constant Contact audience into Drip, respecting every opt-out

**Objective:** Bring a Constant Contact list into Drip. Take the members of the list named `{list-name}` who can still be emailed, find the ones Drip does not have, and after confirmation create them in Drip tagged `{tag}` (default the list name).

**Step 1: Read the list**

Call `constant-contact-get-contact-list` with `name` set to `{list-name}`. If nothing matches exactly, call it again with `name.contains`, list the matches and stop so the user can pick. Then call `constant-contact-get-contact-list-member` with `list-id` set to the list's `list-id`. Keep only members whose `permission-to-send` is explicit or implicit.

**Step 2: Check each against Drip**

For each kept member, call `drip-get-subscriber` with `email` set to their `email-address`. Split them into: already in Drip (note their Drip `status`) and missing from Drip.

**Step 3: Confirm**

Show the counts (list members, mailable, already in Drip, missing) and a table of the missing people: email, first name, last name. Ask: "Create these N people in Drip tagged with the tag?" Do nothing until the user says yes.

**Step 4: Write and confirm**

For each confirmed person, call `drip-add-subscriber` once with `email`, `first_name` and `last_name` from Constant Contact, `tags` set to the tag, and `status` set to active. Re-read each with `drip-get-subscriber` and confirm the person exists.

**Step 5: Report**

A table: email, result (created, already in Drip, skipped as unsubscribed, failed).

**Rules & Guidelines:**

* `constant-contact-get-contact-list` and `constant-contact-get-contact-list-member` are on the constant-contact server. `drip-get-subscriber` and `drip-add-subscriber` are on the drip server.
* The only write allowed is `drip-add-subscriber`, after Step 3, and only for people missing from Drip.
* Never create anyone whose Constant Contact `permission-to-send` is unsubscribed or blank. Never re-create or update someone Drip already has, even if Drip shows them unsubscribed: that would override their opt-out.
* Do NOT call `drip-update-subscriber`, `drip-add-subscriber-to-campaign` or any constant-contact- action.

**Validation:**

* If the list has no mailable members, say so and stop.
* If everyone is already in Drip, say so and stop without writing.
* If more than 200 people are missing, show the first 200 and ask before continuing in batches.