Keep BugHerd tasks and Bugsnag errors in step

**Objective:** Bring linked BugHerd tasks in the project `{project-name}` and their Bugsnag errors back in step.

How the two systems are linked: a BugHerd task created from a Bugsnag error carries "bugsnag:<error id>" in its external-id, and the Bugsnag error is linked to the task's admin-link with `bugsnag-link-error-issue`.

**Step 1: Read the links**

Call `bugherd-get-projects` with `name.contains` set to `{project-name}`. If nothing matches, say so and stop. If several match, list their names and project-id values and ask which one; do not guess. Then call `bugherd-get-tasks` and `bugherd-get-archived-tasks` with `project-id` and `max-records` 500, keeping tasks whose external-id starts with "bugsnag:". For each, call `bugsnag-get-error` with `error-id`.

**Step 2: Propose**

* Task done, closed or archived and the error still open: mark the error fixed. If the error has new events since the task was closed, flag it as "may have regressed" instead and do not propose fixing it.
* Error fixed or ignored and the task still open: set the task's status to done with the comment "Bugsnag error <error id> is <status>."

Show the proposals in one table and ask which rows to apply.

**Step 3: Apply approved rows**

* Bugsnag: Bugsnag write tools need the Bugsnag project-id, which `bugsnag-get-error` does not return: call `bugsnag-get-project` with `name` set to the error's project-name to get it. Then call `bugsnag-fix-error` once with `project-id` and `error-id`.
* BugHerd: call `bugherd-update-task` once with `project-id`, `task-id` and `status` done, then `bugherd-add-comment` once.

**Step 4: Report**

What changed on each side, regressions flagged, and anything that failed.

**Rules & Guidelines:**

* Tools named bugherd-... are on the bugherd MCP server; tools named bugsnag-... are on the bugsnag MCP server. If either set of tools is missing, say which server is not connected and stop.
* The only write tools this prompt may call are `bugsnag-fix-error`, `bugherd-update-task` and `bugherd-add-comment`, and only for approved rows.
* Never discard, ignore or reopen an error, and never reopen a task.

**Validation:**

* If nothing is out of step, say so and stop.