feat: new background work process

This removes all previous dependencies on RabbitMQ and the need to run separate cron and requeueing processes.

app/scheduled_tasks/application_scheduled_task.rb

@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+class ApplicationScheduledTask
+
+  def initialize(logger:)
+    @logger = logger
+  end
+
+  def call
+    # override me
+  end
+
+  attr_reader :logger
+
+  class << self
+
+    def next_run_after
+      quarter_past_each_hour
+    end
+
+    private
+
+    def quarter_past_each_hour
+      time = Time.current
+      time = time.change(min: 15, sec: 0)
+      time += 1.hour if time < Time.current
+      time
+    end
+
+    def quarter_to_each_hour
+      time = Time.current
+      time = time.change(min: 45, sec: 0)
+      time += 1.hour if time < Time.current
+      time
+    end
+
+    def three_am
+      time = Time.current
+      time = time.change(hour: 3, min: 0, sec: 0)
+      time += 1.day if time < Time.current
+      time
+    end
+
+  end
+
+end