Additional service to store current search results for reuse across modules

Problem/Motivation

We're considering implementing a block that recognises when a given set of search results have a particular facet available, and in cases where those facets exist, we want to list other sites that relate to each facet in turn as an alternative search option. This might only be possible if we define a separate service that stores the current Funnelback search, so that we can reuse it multiple times instead of having to run a separate search for the

Steps to reproduce

N/A, new feature

Proposed resolution

Implement a new service as an intermediary between the funnelback.funnelback service and the code that uses it. This might allow us to store the results of searches and then recall them on demand, depending on context such as whether the search belongs to the whole page or perhaps components of the page.

Remaining tasks

Figure out how best to implement this in a way that's effective and non-intrusive.

User interface changes

Ideally none.

API changes

Ideally none, but we might need to change the way that searches are invoked to allow for this.

Data model changes

No config or database changes, but an extra service would be needed to track searches.