Raise Business Central invoices without billing twice

**Objective:** Create a draft sales invoice for `{customer-name}` for `{lines}`.

Pass `{company}` as the company argument on every call. If `{company}` is empty, leave the company argument out so the connector's default company is used.

**Step 1: Resolve the customer**

Call `business-central-get-customer` with name.contains set to `{customer-name}`. If several match, list them and stop. If blocked is Invoice or All, stop and explain.

**Step 2: Resolve each line**

Each entry in `{lines}` is an item, a G/L account or a resource with a quantity and optionally a price.

* Items: `business-central-get-item` with item-number or description.contains; line-type Item.
* Services billed to an account: `business-central-get-account` with account-number or name.contains; it must be account-type Posting, not blocked, direct-posting true; line-type Account.
* Time: `business-central-get-resource` with resource-number or name.contains, not blocked; line-type Resource.

Stop and ask on no match or several matches.

**Step 3: Duplicate check**

Call `business-central-get-sales-transaction` with sell-to-customer-number and document-type Invoice, and `business-central-get-posted-sales-invoice` with sell-to-customer-number and posting-date.from 7 days ago. If one has a matching external-document-number or the same total, warn that this may be a duplicate.

**Step 4: Preview and confirm**

Show customer, invoice date, due date if the user gave one, lines (type, number, description, quantity, unit price, amount), total, and warnings. Ask for confirmation.

**Step 5: Create**

After confirmation call `business-central-create-sales-invoice` once with customer-number and bill-to-customer-number, invoice-date, and external-document-number or customer-purchase-order-reference when given. Then for each line call `business-central-create-sales-invoice-line` with document-number, line-type, number-on-line, quantity, unit-price and description where given.

**Step 6: Confirm the result**

Call `business-central-get-sales-transaction` with document-number and `business-central-get-sales-transaction-line` with document-number. Report the invoice number and total, and say it is a draft that still has to be posted in Business Central.

**Rules & Guidelines:**

* Do not call any create or update tool until the user has confirmed the exact values shown in the preview.
* Call `business-central-create-sales-invoice` exactly once.

**Validation:**

* If `{lines}` is empty, ask for them first.