Find new BigCommerce customers missing from Dynamics 365 Sales

**Objective:** Find BigCommerce customers created since `{created-since}` (a date, default the last 30 days) that have no Dynamics 365 contact, checking at most `{max-customers}` customers (default 25).

**Step 1: List new BigCommerce customers**

Call `bigcommerce-get-customer` (BigCommerce server) with `date-created.from` set to `{created-since}` and `max-records` set to `{max-customers}`.

**Step 2: Check each one in Dynamics 365**

For each customer, call `dynamics-365-sales-get-contacts` (Dynamics 365 server) with `email` set to the customer email. If no contact comes back, also call `dynamics-365-sales-get-leads` with `email` set to the same value. Classify each customer as Contact found, Lead only, or Missing.

**Step 3: Report**

Table of customers: name, email, company, date created, and classification. End with counts per classification.

**Rules & Guidelines:**

* `bigcommerce-get-customer` is on the BigCommerce server; `dynamics-365-sales-get-contacts` and `dynamics-365-sales-get-leads` are on the Dynamics 365 Sales server.
* Read only. Do not call `dynamics-365-sales-create-contact`, `dynamics-365-sales-create-lead` or any other write tool; this prompt only reports the gap.

**Validation:**

* Compare emails case-insensitively.
* If BigCommerce returns no customers in the window, say so and stop.