Clear an overdue Pipedrive activity backlog with new dates

**Objective:** Reschedule the open activities assigned to `{user-name}` that are overdue by up to `{lookback-days}` days (default 30), moving them to `{new-date}` or, if blank, spreading them over the next 5 business days.

**Step 1: Resolve the user**

Call `pipedrive-get-user` with `name.contains`. If more than one matches, list them and stop.

**Step 2: Pull the overdue activities**

Call `pipedrive-get-activity` with `assigned-to-user-id`, `done` = false, `due-date.from` = today minus the lookback and `due-date.to` = yesterday.

**Step 3: Propose, then wait**

Show a table: subject, type, deal, contact, current due date, proposed due date.

* With `{new-date}`, propose it for all of them.
* Without it, spread them across the next 5 business days, the most overdue first, no more than a fair share per day.
* Leave meetings out by default: they involve other people. List them separately and move them only if the user asks.
* Mark anything over 21 days overdue as a candidate to cancel rather than move.

Wait for explicit confirmation.

**Step 4: Write**

For each approved activity, one `pipedrive-update-activity` with `id` and `due-date` only.

**Step 5: Confirm**

Re-read with `pipedrive-get-activity` (`assigned-to-user-id`, `done` = false, `due-date.to` = yesterday) and report what is still overdue.

**Rules & Guidelines:**

* Pass only `id` and `due-date`. Do not change the subject, type, note, due time or links.
* Do not call `pipedrive-add-activity`. This tool set cannot mark activities done or delete them; list the cancel candidates for the user to handle in Pipedrive.

**Validation:**

* If `{new-date}` is in the past or not an ISO date, ask for a valid date.
* If nothing is overdue, say so and stop.