Give marketing a customer's billing status before they reach out

**Objective:** Summarise the Rillet billing status of the customer whose name contains `{customer-name}` and, after the user confirms, save it as a note on their Constant Contact contact (optionally only the contact with email `{email-address}`), so marketing can see billing context before contacting them.

**Step 1: Identify the customer in Rillet**

Call `rillet-get-customers` (rillet server) and keep rows whose `name` contains `{customer-name}`, ignoring case. If several match, list them with `name` and `customer-id` and ask which one. If none match, say so and stop.

**Step 2: Build the billing summary**

Call `rillet-get-invoices` (rillet server) and keep invoices for the `customer-id`. Count open invoices (`amount-due` above 0), count overdue ones (`overdue` true), and total `amount-due` by `currency`. Call `rillet-get-arr-waterfall` (rillet server) with `customer-id` and take the latest `year-month`, `arr` and `currency`. Call `rillet-get-contracts` (rillet server) with `customer-id` and note any active contract's `end-date`.

Write the note as plain text, at most five lines, for example:

Billing status (Rillet) as of <today>: 2 open invoices, 1 overdue since <date>. Amount due: <amount> <currency>. ARR: <amount> <currency>. Contract ends <date>.

**Step 3: Find the Constant Contact contact**

Call `rillet-get-customer-emails` (rillet server) and keep the emails for the `customer-id`. If `{email-address}` is given, keep only that one. For each email, call `constant-contact-get-contact` (constant-contact server) with `email-address`. If no email resolves to a contact, report the summary and stop: this prompt does not create contacts.

**Step 4: Confirm**

Show the note text and the contact(s) it will be added to (name, email, `contact-id`). Ask the user to confirm. Do not continue without an explicit yes.

**Step 5: Write and verify**

For each confirmed contact, call `constant-contact-add-contact-note` (constant-contact server) once with `contact-id` and `content` set to the note. Then call `constant-contact-get-contact-note` with `contact-id` and confirm the note is there.

**Rules & Guidelines:**

* Tools starting rillet- are on the rillet server; tools starting constant-contact- are on the constant-contact server.
* `constant-contact-add-contact-note` is the only tool that may write, once per contact, after the confirmation in Step 4.
* Do not call `constant-contact-update-contact`, `constant-contact-add-contact` or any other constant-contact-add-* or constant-contact-update-* tool, and do not call `rillet-update-customer`, `rillet-set-invoice-sent-status` or any other rillet-add-* or rillet-update-* tool.
* Keep the note factual: no judgement words such as "bad payer".

**Validation:**

* If the customer has no open invoices and no ARR, still offer the note, stating "No open balance".
* Never add amounts in different currencies.