app/views/hunters_improvements/_form.html.erb
<%= form_with(model: [hunters_improvement.hunter, hunters_improvement], local: true) do |form| %>
<%= render 'layouts/errors', errors: hunters_improvement.errors %>
<hunters-improvement-form hunter_id="<%= hunters_improvement.hunter.id %>" :improvements="<%= @improvements.to_json %>"></hunters-improvement-form>
<div class="actions">
<%= form.submit class: 'button' %>
</div>
<% end %>