Display agreements

[ajparsons]

This PR adds basic support for displaying agreements in the Policy-for-MP page:

This doesn't directly deal with if agreements score for policies - that can be enabled after #1755 is merged however.

[dracos]

Couple of tiny things. Nice to have a way to include these!
Only minor structural thing, and much easier the way you've done it, is that it feels like you'd want to have a Policy object containing its divisions and its agreements together. But I don't suggest trying to rejig everything to enable that :)

[ajparsons]

Only minor structural thing, and much easier the way you've done it, is that it feels like you'd want to have a Policy object containing its divisions and its agreements together. But I don't suggest trying to rejig everything to enable that :)

Just for revisiting when this isn't fixed in 10 years time - do you mean like a policy->decisions that is a list of both?

In twfy-votes, there's a PolicyDecisionLink that can be specialised for Divisions or Agreements - the Policy object maintains two lists, but they can be combined easier. So could pull that concept back in at some point.

https://github.com/mysociety/twfy-votes/blob/main/src/twfy_votes/apps/policies/models.py#L163-L167

[dracos]

do you mean like a policy->decisions that is a list of both?

Sorry, no, wasn't clear, I didn't mean they'd be together as one list, but that they'd both be under one object for the policy, rather than be in two different things under Policies

[ajparsons]

Fixup commit fixes indenting