Add feed link to show page

lib/frenzy_web/templates/feed/show.html.eex

@@ -2,7 +2,9 @@
   <%= if @feed.favicon do %>
     <img src="<%= @feed.favicon %>" alt="<%= @feed.title %> favicon" class="favicon">
   <% end %>
-  <%= @feed.title %>
+  <a href="<%= feed_site_url(@feed) %>">
+    <%= @feed.title %>
+  </a>
 </h1>
 
 <%= form_tag Routes.feed_path(@conn, :refresh, @feed.id), method: :post, class: "d-inline" do %>

lib/frenzy_web/views/feed_view.ex

@@ -1,3 +1,13 @@
 defmodule FrenzyWeb.FeedView do
   use FrenzyWeb, :view
+  alias Frenzy.Feed
+
+  @spec feed_site_url(feed :: Feed.t()) :: String.t()
+  def feed_site_url(%Feed{site_url: site_url}) when is_binary(site_url) do
+    site_url
+  end
+
+  def feed_site_url(%Feed{feed_url: feed_url}) do
+    URI.merge(feed_url, "/") |> to_string()
+  end
 end