Reconcile 2Checkout customers with Constant Contact contacts

**Objective:** Compare 2Checkout customers (optionally only those at company `{company}`, up to `{max-records}` customers, default 50) with Constant Contact contacts and report who is missing from each system.

**Step 1: Read customers from 2Checkout**

Call `2checkout-get-customer` with `company` set to `{company}` if given, and `max-records` set to `{max-records}` (50 if empty). Keep `customer-reference`, `first-name`, `last-name`, `email` and `enabled`. Set aside customers with no email and count them.

**Step 2: Look each customer up in Constant Contact**

For each customer email, call `constant-contact-get-contact` with `email-address` set to that email. Record `contact-id`, `first-name`, `last-name` and `permission-to-send` when a contact comes back. If nothing comes back, mark the customer as absent from Constant Contact and continue.

**Step 3: Look for contacts that are not customers**

Call `constant-contact-get-contact` with `max-records` set to `{max-records}` and, for each contact whose `email-address` was not seen in Step 1, call `2checkout-get-customer` with `email` set to that address. Mark contacts that return nothing as not a 2Checkout customer.

**Step 4: Report**

Give four lists: matched customers (with any name mismatch between the systems), customers missing from Constant Contact, contacts that are not 2Checkout customers, and customers skipped for having no email. End with the counts.

**Rules & Guidelines:**

* Tools whose names start with 2checkout belong to the 2checkout server and tools whose names start with constant-contact belong to the Constant Contact server. Both servers must be connected.
* The shared key is the email address: 2checkout `email` / `end-user-email` / `billing-email` against Constant Contact `email-address`. Compare emails case-insensitively after trimming spaces.
* This is read-only. Never call any 2checkout action tool (any 2checkout tool that adds, updates, cancels, refunds, enables or disables) and never call `constant-contact-add-contact`, `constant-contact-update-contact`, `constant-contact-add-contact-note`, `constant-contact-add-contact-list`, `constant-contact-update-contact-list`, `constant-contact-add-contact-tag`, `constant-contact-update-contact-tag`, `constant-contact-add-campaign`, `constant-contact-update-campaign` or `constant-contact-resend-campaign-to-non-openers`.

**Validation:**

* If `2checkout-get-customer` returns nothing, say so and stop.
* If an email matches more than one contact or customer, list the duplicates and do not pick one.
* Say that Step 3 only covers the first `{max-records}` contacts, so it is a sample, not a full audit.