Reconcile a customer's Chargebee and GP receivables

**Objective:** Reconcile the receivables owed by {customer} in PowerGP against the open Chargebee invoices and report any difference. Look at the last {lookback-days} days of Chargebee invoices (default 90).

**Step 1: Find the customer in PowerGP**

Call `powergp-online-get-customers` (powergp-online-ai) with `customer-name.contains` set to the customer, or `customer-number` if the value looks like an account number. If more than one matches, list them and stop. Note `customer-number`, `customer-name` and `balance-due`.

**Step 2: Find the customer in Chargebee**

Call `chargebee-get-customer` (chargebee) with `company.contains` set to the PowerGP `customer-name`. If nothing matches, retry with `email.contains` if the user gave an email. If still nothing, report the customer as present in PowerGP and absent from Chargebee and stop. If several match, list them and stop.

**Step 3: Pull the open items on both sides**

Call `powergp-online-get-receivablestransactions` with `customer-number` from step 1 and read `document-number`, `document-date`, `document-amount`, `unapplied-amount`, `days-past-due`. Call `chargebee-get-invoice` with `customer-id` from step 2, `date.from` set to the lookback start, and read `id`, `status`, `total`, `amount-due`, `due-date`.

**Step 4: Report**

Give a table of Chargebee invoices with amount due and the PowerGP document that appears to match (same amount and date within 7 days, or the invoice id in the document number). Then list unmatched items on each side, and the total outstanding in each system and the gap.

**Rules & Guidelines:**

* Tools prefixed powergp-online- belong to the powergp-online-ai server; tools prefixed chargebee- belong to the chargebee server. Both servers must be connected.
* Read-only: call only the get tools named above. Never create, change or delete anything in either system.
* Never print card or bank details; report ids, names and amounts only.

**Validation:**

* If either side returns no rows, say so and still report the other side.
* If currencies differ (`currency-id` against `currency-code`), do not compare totals; show each in its own currency.