Get missing Stripe invoices into Rillet without recording one twice

**Objective:** Find the Stripe invoices created from {from-date} to {to-date} (default today) that do not exist in Rillet, and after the user confirms, record each one in Rillet as an external invoice recorded as {record-as}.

{record-as} must be ar-only (Rillet tracks the receivable and revenue is recognised elsewhere) or revenue-only (Rillet recognises the revenue and the receivable stays in Stripe). If it is anything else, explain the two options and stop.

**Step 1: Find the gap**

Call `stripe-get-invoice` with `created-date.from` = {from-date} and, if given, `created-date.to` = {to-date}. Keep only invoices with status open or paid. Call `rillet-get-invoices` (it takes no filters) and drop every Stripe invoice whose number already equals a Rillet invoice-number. Only exact number matches count; never skip or create an invoice on a fuzzy match.

**Step 2: Resolve the Rillet customer**

Call `rillet-get-customer-emails` and match the Stripe customer-email to email, ignoring case. If there is no email match, call `rillet-get-customers` and match the Stripe customer-name to name exactly, ignoring case. If there is no match or more than one, do not record the invoice: list it under Needs a customer in Rillet. Do not create customers.

**Step 3: Build the lines**

Call `stripe-get-invoice-item` with `invoice-id` = the Stripe invoice-id. For each line, call `stripe-get-product` with its `product-id` to get the product name, then find the Rillet product with exactly that name in `rillet-get-products` (no filters). If any line has no Rillet product, list the invoice under Needs a product in Rillet and skip it. Rillet takes at most three lines: when there are more, combine lines that share a Rillet product by summing their amounts and quantities; if there are still more than three, skip the invoice and say why.

**Step 4: Preview and confirm**

Show one table row per invoice to be recorded: Stripe number, Rillet customer, invoice date, due date, and each line's Rillet product, quantity, total, currency and service period. Ask the user to confirm. Write nothing until they say yes; they may confirm a subset.

**Step 5: Record**

For each confirmed invoice, one call at a time, call `rillet-add-invoice-ar-only` when {record-as} is ar-only, or `rillet-add-invoice-revenue-only` when it is revenue-only, with:

* external-system = Stripe, external-id = the Stripe invoice-id, external-url = the Stripe hosted-invoice-url
* invoice-number = the Stripe number, invoice-date = the Stripe created-date, due-date = the Stripe due-date
* customer-id = the Rillet customer-id from Step 2
* for each line: product-id (Rillet), quantity, total, currency in upper case, description, and revenue-start / revenue-end from the Stripe period-start / period-end

If a call fails, stop, report the error and list what was and was not recorded.

**Step 6: Confirm**

Call `rillet-get-invoices` again and check each recorded invoice-number is now present. Report recorded, skipped (with the reason) and failed.

**Rules & Guidelines:**

* `stripe-get-invoice`, `stripe-get-invoice-item` and `stripe-get-product` are on the stripe server and are read-only. Every other tool named here is on the rillet server.
* The only tools that may write are `rillet-add-invoice-ar-only` or `rillet-add-invoice-revenue-only`, whichever {record-as} names, and only after the Step 4 confirmation.
* Do not call `rillet-add-invoice`, `rillet-update-invoice`, `rillet-add-customer`, `rillet-add-product` or `rillet-add-invoice-payment`. Payments are recorded by the apply-stripe-payments prompt.

**Validation:**

* If every Stripe invoice already exists in Rillet, say so and stop.
* Stripe may return amounts in the smallest currency unit. If an invoice's line amounts do not add up to its total but do when divided by 100, divide by 100, and say so in the preview.
* If a tool cannot be found, name the server it belongs to (rillet or stripe) and stop.