See a customer's full history across GP and Intacct

**Objective:** Give a single history for customer `{customer-id}` covering the last `{months-back}` months (default 12), with GP activity before cutover and Intacct activity after, and flag settings that did not carry across.

**Step 1: The customer in both systems**

Call `dynamics-gp-get-rm-customer` with `customer-id` = `{customer-id}` and `intacct-get-customer` with the same `customer-id`. If Intacct has no match, try `customer-name` from GP; if still none, say the customer was not migrated and continue with GP only.

Compare payment terms (`payment-terms-id` vs `term`), credit limit (`credit-limit-amount` vs `credit-limit`), status, email and city. List every difference.

**Step 2: GP history**

Call `dynamics-gp-get-rm-trx` and `dynamics-gp-get-rm-sales-trx` for the customer, `document-date.from` = `{months-back}` months ago. Keep document number, type, date, amount and open amount.

**Step 3: Intacct history**

Call `intacct-get-invoice`, `intacct-get-ar-payment` and `intacct-get-order-entry-document` for the customer over the same period.

**Step 4: Merge**

Use `{cutover-date}` to split the timeline. If it is empty, take the day after the latest GP document date and say it was inferred. Open invoices migrated at cutover appear in both systems: match GP `document-number` to Intacct `invoice-number` or `reference-number` and show each once, tagged "migrated".

**Step 5: Report**

1. Customer header, and the setting differences from Step 1.
2. Monthly totals, sales and payments, tagged GP or Intacct per month.
3. Current open balance (Intacct), and any open GP document that did not migrate.
4. The last 10 documents with their source.
5. A one-line read: is the customer buying more, less or the same since cutover, and are they paying on time.

**Rules & Guidelines:**

* Tools prefixed dynamics-gp- are on the dynamics-gp MCP server. Tools prefixed intacct- are on the intacct MCP server. Both servers must be connected; if a tool from either is missing, say which server is not connected and stop.
* Pass `{gp-company}` as `company` on every dynamics-gp- call (empty means the default GP company). Use the default Intacct company; if the Intacct side holds several entities and it is not clear which one received this GP company, ask before starting.
* Set `max-records` high (5000) on every list read. If a read returns exactly that many rows, say the result may be truncated and narrow the filter (per account, per vendor, per customer or per item) instead of reporting totals from it.
* Read only. Do NOT call `intacct-update-customer`, `intacct-create-order-entry-document`, `dynamics-gp-rm-customer-update` or `dynamics-gp-rm-sales-trx-add`.

**Validation:**

* If the customer is not in GP, say so and report Intacct only; they may be a new customer.
* Never add a migrated invoice to both sides of a monthly total.