feat: Allow users to create dashboard apps to give agents more context (#4761)

db/migrate/20220525141844_create_dashboard_apps.rb

@@ -0,0 +1,11 @@
+class CreateDashboardApps < ActiveRecord::Migration[6.1]
+  def change
+    create_table :dashboard_apps do |t|
+      t.string :title, null: false
+      t.jsonb :content, default: []
+      t.references :account, null: false, foreign_key: true
+      t.references :user, foreign_key: true
+      t.timestamps
+    end
+  end
+end