Notify user when item(s) are aged to lost (automated f/f)

Current situation or problem:
The only automated fee/fine notice that's been implemented is an overdue fee/fine that's triggered when the overdue fee/fine is charged upon return or renewal by patron. Eventually, if an item isn't returned after it's overdue, it's automatically aged to lost by the system. We need notices to support this feature.

Use case(s):

• As library staff, I want to send a notice to all patrons that have borrowed items with a status change to "aged to lost."
• As library staff, I want to send reminder notices to all patrons that have borrowed items with a status of "aged to lost" (until that item is charged a fee/fine).
• As library staff, I want to send a notice to all patrons charged lost item fee/fine(s), including amount to charge for the item and/or associated processing fees, as single notice.
• As library staff, I want to send a notice to all patrons with adjusted lost item fee/fine(s) due to the item(s) being replaced or returned.

These are notices to support UXPROD-1857 and UXPROD-87.

In scope:

• Need to send a notice when item status is changed to "aged to lost."
• Need to send notices reminding a patron that an item's status has been changed to "aged to lost."
• Need to send a notice when a lost item fee/fine (and it's associated processing fees, if applicable per policy) are charged to patron.
• Need to send a notice when adjustments are made to a lost item fee/fine, such as (and again, if applicable per lost item fee policy):
  • If lost item returned, remove lost item processing fee - cancel or refund if paid (fully or partially)
  • If lost item replaced, remove lost item processing fee - cancel or refund if paid (fully or partially)
  • If replacements are allowed and a replacement processing fee is charged
• Need to adjust processing fees associated with the lost item (set cost) as defined by the policy (see above) and any reminder notices need to reflect any adjustments

Out of scope:

• Actual cost fees/fines (instead of set cost) notices (blocked by UXPROD-2572)
• Statements including status of all (outstanding) fees/fines by patron (UXPROD-2113)

Proposed solution/stories:

• BE story for storage of new triggers
• BE stories for processing/logic of new triggers
• FE story to add new triggers to UI
• New triggers:
  • Add a new trigger under loan in notice policy titled "Aged to lost"
  • Add a new trigger under fee/fine in notice policy titled "Aged to lost fee/fine" (NOTE: might include the charge for the item plus a processing fee)
  • Add a new trigger under fee/fine in notice policy titled "Aged to lost & returned - adjusted fee/fine"
  • Add a new trigger under fee/fine in notice policy titled "Aged to lost & replaced - adjusted fee/fine"

Preferably needs to support multiple fee/fines for each patron due to one or more associated fees (set cost plus processing fees). Also, if a patron has several items meeting the aged to lost fee/fine policy criteria, then these should be bundled into a single notice. See UXPROD-2252.