Find donor calls in Chorus that never reached Bloomerang

**Objective:** List every Chorus conversation in the last `{lookback-days}` days (default 30) that involved a Bloomerang constituent but has no matching Bloomerang interaction, optionally limited to conversations owned by the Chorus user `{rep-email}` (if empty, include every user).

**Step 1: List the conversations in Chorus**

Call `chorus-get-engagements` with `date.from` set to the start of the window and, if `{rep-email}` is given, `user-email` set to it. Use `max-records` 50. If the result is capped at 50, say so in the report and suggest a shorter window.

**Step 2: Find the donors on each conversation**

For each conversation, call `chorus-get-conversation-participants` with its `conversation-id`. Keep external participants only (no `user-id`, and not typed as internal). For each distinct external email, call `bloomerang-get-email-address` with `value` set to it and take `account-id`. Cache the result so each email is looked up once.

**Step 3: Check Bloomerang for a logged interaction**

For each conversation and matched account id, call `bloomerang-get-interaction` with `account-id`, and with `date.from` and `date.to` set to one day either side of the conversation date. The conversation counts as logged if any interaction comes back in that range.

**Step 4: Report**

* A table of unlogged conversations: date, subject, Chorus owner (`user-name`), constituent name, Bloomerang account id, `conversation-id`.
* A count of conversations checked, logged, unlogged, and with no Bloomerang match at all.
* Per Chorus owner: how many of their donor conversations are unlogged.
* Close by suggesting the `log-conversation-to-bloomerang` prompt for any row the user wants recorded.

**Rules & Guidelines:**

* Tools whose names start with chorus are on the chorus server; tools whose names start with bloomerang are on the bloomerang server.
* This prompt is read-only. Do not call `bloomerang-add-interaction`, `bloomerang-add-note`, `bloomerang-add-task` or any other Bloomerang add or update tool, and do not call any Chorus action such as `chorus-add-moment`.
* Conversations whose participants match no constituent are not unlogged donor conversations; count them separately and do not list them individually.

**Validation:**

* If Chorus returns no conversations in the window, say so and stop.
* Chorus dates carry a time; compare by calendar day. Match emails case-insensitively.