Fixes #135

Adds a table with proposed actions in the dashboard. The user can mark
an action as executed.

spec/models/proposal_executed_dashboard_action_spec.rb

@@ -0,0 +1,41 @@
+# frozen_string_literal: true
+require 'rails_helper'
+
+describe ProposalExecutedDashboardAction do
+  subject do 
+    build :proposal_executed_dashboard_action, 
+          proposal: proposal,
+          proposal_dashboard_action: proposal_dashboard_action,
+          executed_at: executed_at
+  end
+
+  let(:proposal) { create :proposal }
+  let(:proposal_dashboard_action) { create :proposal_dashboard_action }
+  let(:executed_at) { Time.now }
+
+  it { is_expected.to be_valid }
+
+  context 'when proposal is nil' do
+    let(:proposal) { nil }
+
+    it { is_expected.not_to be_valid }
+  end
+
+  context 'when proposal_dashboard_action is nil' do
+    let(:proposal_dashboard_action) { nil }
+
+    it { is_expected.not_to be_valid }
+  end
+
+  context 'when executed_at is nil' do
+    let(:executed_at) { nil }
+
+    it { is_expected.not_to be_valid }
+  end
+
+  context 'when it has been already executed' do
+    let!(:executed) { create(:proposal_executed_dashboard_action, proposal: proposal, proposal_dashboard_action: proposal_dashboard_action) }
+
+    it { is_expected.not_to be_valid }
+  end
+end