add newsletter and email campaigns

Subscribers with double opt-in confirmation, campaign composer with
draft/scheduled/sent lifecycle, admin dashboard with overview stats,
CSV export, and shop signup form wired into page builder blocks.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

test/berrypod_web/controllers/newsletter_controller_test.exs

@@ -0,0 +1,96 @@
+defmodule BerrypodWeb.NewsletterControllerTest do
+  use BerrypodWeb.ConnCase, async: true
+
+  alias Berrypod.Newsletter
+  alias Berrypod.Newsletter.Subscriber
+  alias Berrypod.Repo
+
+  describe "POST /newsletter/subscribe" do
+    test "subscribes and redirects back", %{conn: conn} do
+      Newsletter.set_newsletter_enabled(true)
+
+      conn =
+        conn
+        |> put_req_header("referer", "http://localhost:4002/")
+        |> post(~p"/newsletter/subscribe", %{email: "new@example.com"})
+
+      assert redirected_to(conn) == "/"
+      assert Phoenix.Flash.get(conn.assigns.flash, :info) =~ "Check your inbox"
+    end
+
+    test "handles already confirmed subscriber", %{conn: conn} do
+      Newsletter.set_newsletter_enabled(true)
+
+      # Create a confirmed subscriber directly
+      now = DateTime.utc_now() |> DateTime.truncate(:second)
+
+      %Subscriber{}
+      |> Subscriber.changeset(%{
+        email: "confirmed@example.com",
+        status: "confirmed",
+        confirmed_at: now
+      })
+      |> Repo.insert!()
+
+      conn =
+        conn
+        |> put_req_header("referer", "http://localhost:4002/about")
+        |> post(~p"/newsletter/subscribe", %{email: "confirmed@example.com"})
+
+      assert redirected_to(conn) == "/about"
+      assert Phoenix.Flash.get(conn.assigns.flash, :info) =~ "already subscribed"
+    end
+
+    test "shows error for invalid email", %{conn: conn} do
+      Newsletter.set_newsletter_enabled(true)
+
+      conn =
+        conn
+        |> put_req_header("referer", "http://localhost:4002/")
+        |> post(~p"/newsletter/subscribe", %{email: "not-an-email"})
+
+      assert redirected_to(conn) == "/"
+      assert Phoenix.Flash.get(conn.assigns.flash, :error) =~ "valid email"
+    end
+
+    test "redirects to / when no referer", %{conn: conn} do
+      Newsletter.set_newsletter_enabled(true)
+
+      conn = post(conn, ~p"/newsletter/subscribe", %{email: "test@example.com"})
+
+      assert redirected_to(conn) == "/"
+    end
+  end
+
+  describe "GET /newsletter/confirm/:token" do
+    test "confirms pending subscriber", %{conn: conn} do
+      # Create a pending subscriber with a known raw token
+      raw_token = "test-confirmation-token-abc123"
+      hashed_token = :crypto.hash(:sha256, raw_token) |> Base.encode16(case: :lower)
+
+      %Subscriber{}
+      |> Subscriber.changeset(%{
+        email: "pending@example.com",
+        status: "pending",
+        confirmation_token: hashed_token
+      })
+      |> Repo.insert!()
+
+      conn = get(conn, "/newsletter/confirm/#{raw_token}")
+
+      assert conn.status == 200
+      assert conn.resp_body =~ "subscribed"
+
+      # Verify the subscriber is now confirmed
+      sub = Repo.get_by!(Subscriber, email: "pending@example.com")
+      assert sub.status == "confirmed"
+    end
+
+    test "returns error for invalid token", %{conn: conn} do
+      conn = get(conn, "/newsletter/confirm/invalid-token-here")
+
+      assert conn.status == 400
+      assert conn.resp_body =~ "invalid"
+    end
+  end
+end