Notification of unclaimed output requests

## User Story
**As an** _output checker_,

**I want** _to be notified if no one claims a request after a certain time period_

**so that** _I minimize risk that I have missed, or overlooked an urgent output request_.

# Conditions of Satisfaction
- notification time period is configurable by administrators
- notification time period begins when the output is created
- notification time period ends after time-output-created + number-of-hours
- notification repetition has a limit
- notification template is distinct

Start by tracing where output requests are created and how administrators configure notifications. Identify the existing notification delivery and template entry points, then define how configurable timing, repetition limits, and the distinct template should be represented and verified.

Written by the indexing model from the issue text.