Assign Bugsnag errors to someone who can actually see them

**Objective:** Assign the Bugsnag error `{error-id}` in project `{project-name}` to the collaborator `{collaborator-name}`. This prompt changes data.

**Step 1: Resolve the project id**

Call `bugsnag-get-project` with `name` set to `{project-name}` and keep its `project-id`. `bugsnag-get-error` returns only the project name, so the id has to come from here.

**Step 2: Resolve the collaborator id**

Call `bugsnag-get-project-collaborator` with `project-name` set to the resolved project name and `collaborator-name.contains` set to `{collaborator-name}`, and keep the `collaborator-id`. If that returns nothing, call `bugsnag-get-collaborator` with `name.contains` instead: a match there means the person exists in the organization but has no access to this project, which you must say rather than working around. If more than one person matches, list them with their emails and stop.

**Step 3: Confirm the error**

Call `bugsnag-get-error` with `error-id` set to `{error-id}` and show the user the error class, message, severity and the collaborator you are about to assign it to. Wait for confirmation.

**Step 4: Assign**

Call `bugsnag-assign-error` with the `project-id` from Step 1, `error-id` `{error-id}` and `assigned-collaborator-id` from Step 2. Report what was assigned to whom.

**Rules & Guidelines:**

* Never guess a collaborator id or a project id. Both are resolved by a read first.
* Do not call `bugsnag-add-project-collaborator` to grant the person access so the assignment will work. If they lack access, report that and stop; granting access is somebody's decision.
* Do not change the error's status or severity while assigning it.

**Validation:**

* If the collaborator has a pending invitation, say so before assigning; they may never see it.
* If the error is already assigned, say to whom and ask whether to reassign.