Search or filter annotations by date

Requested by user https://app.hubspot.com/contacts/6291320/ticket/463065348/

Feature request to allow users to search and/or filter annotations based on date modifiers. E.g. Older that 6/1/2020, between 1/15/20 and 1/31/20, last 7 days, etc.

The issue names no files or tests; start by locating the annotation search and filtering entry point. Clarify which date modifiers and boundary rules are required, then trace how annotations are queried. Done means users can filter or search annotations by the agreed date ranges, with coverage for the stated examples.

Written by the indexing model from the issue text.