The `use_helpers` method was added in ViewComponent 3.8.0, and it's
included by default in all components since version 3.11.0.
Note we sometimes delegated the `can?` method to the controller instead
of the helpers, for no particularly reason. We're unifying that code as
well.
As far as possible I think the code is clearer if we use CRUD actions
rather than custom actions. This will make it easier to add the action
to remove votes in the next commit.
Note that we are adding this line as we need to validate it that a vote
can be created on a debate by the current user:
```authorize! :create, Vote.new(voter: current_user, votable: @debate)```
We have done it this way and not with the following code as you might
expect, as this way two votes are created instead of one.
```load_and_authorize_resource through: :debate, through_association: :votes_for```
This line tries to load the resource @debate and through the association
"votes_for" it tries to create a new vote associated to that debate.
Therefore a vote is created when trying to authorise the resource and
then another one in the create action, when calling @debate.vote_by (which
is called by @debate.register_vote).
In order to reduce the code used to add styles to the buttons,
we removed the classes that had been added and handled it with
the new aria-pressed attribute
We were using the same code to render links to agree and disagree, so we
can extract a new component for this code.
We're also adding component tests to make it easier to test whether
we're breaking anything while refactoring, although the code is probably
already covered by system tests.
Since the votes mixin was only used in one place, we're removing it and
moving most of its code to a new CSS file for the shared component.
