feat: use most recent court date in modal

On the case show page it should autofill the start date of
the date range with the most recent court date.

This most closely mirrors existing behavior.

app/models/casa_case.rb

@@ -158,6 +158,12 @@ def most_recent_past_court_date
     court_dates.where("date < ?", Date.today).order(:date).last
   end
 
+  def formatted_latest_court_date
+    most_recent = most_recent_past_court_date&.date&.in_time_zone || Time.zone.now
+
+    most_recent.strftime(::DateHelper::RUBY_MONTH_DAY_YEAR_FORMAT)
+  end
+
   def has_judge_name?
     judge_name
   end

app/views/casa_cases/_generate_report_modal.html.erb

@@ -22,7 +22,7 @@
         <div class="field form-group mb-20">
           <h6><label class="form-label" for="start_date">Starting From</label></h6>
           <%= form.text_field :start_date,
-            value: Time.zone.now.strftime(::DateHelper::RUBY_MONTH_DAY_YEAR_FORMAT),
+            value: @casa_case.formatted_latest_court_date,
             data: { provide: "datepicker",
                     date_format: ::DateHelper::JQUERY_MONTH_DAY_YEAR_FORMAT },
                     class: "form-control" %>

spec/models/casa_case_spec.rb

@@ -297,6 +297,34 @@
     end
   end
 
+  describe "#formatted_latest_court_date" do
+    let(:casa_case) { create(:casa_case) }
+
+    before do
+      travel_to Date.new(2021, 1, 1)
+    end
+
+    context "with a past court date" do
+      it "returns the latest past court date as a formatted string" do
+        most_recent_past_court_date = create(:court_date, date: 3.months.ago)
+
+        casa_case.court_dates << create(:court_date, date: 9.months.ago)
+        casa_case.court_dates << most_recent_past_court_date
+        casa_case.court_dates << create(:court_date, date: 15.months.ago)
+
+        expect(casa_case.formatted_latest_court_date).to eq("October 01, 2020") # 3 months before 1/1/21
+      end
+    end
+
+    context "without a past court date" do
+      it "returns the current day as a formatted string" do
+        allow(casa_case).to receive(:most_recent_past_court_date).and_return(nil)
+
+        expect(casa_case.formatted_latest_court_date).to eq("January 01, 2021")
+      end
+    end
+  end
+
   context "#remove_emancipation_category" do
     let(:casa_case) { create(:casa_case) }
     let(:emancipation_category) { build(:emancipation_category) }