fix: translation of login page

lib/mv_web/controllers/join_confirm_html/confirm.html.heex

@@ -0,0 +1,65 @@
+<%!-- Public header (same structure as Layouts.app unauthenticated branch) --%>
+<header class="flex items-center gap-3 p-4 border-b border-base-300 bg-base-100">
+  <img src={~p"/images/mila.svg"} alt="Mila Logo" class="size-8 shrink-0" />
+  <span class="menu-label text-lg font-bold truncate flex-1">
+    {@club_name}
+  </span>
+  <form method="post" action={~p"/set_locale"} class="shrink-0">
+    <input type="hidden" name="_csrf_token" value={@csrf_token} />
+    <select
+      name="locale"
+      onchange="this.form.submit()"
+      class="select select-sm focus:outline-none focus:ring-2 focus:ring-primary focus:ring-offset-2"
+      aria-label={gettext("Select language")}
+    >
+      <option value="de" selected={Gettext.get_locale() == "de"}>Deutsch</option>
+      <option value="en" selected={Gettext.get_locale() == "en"}>English</option>
+    </select>
+  </form>
+</header>
+
+<main class="px-4 py-8 sm:px-6">
+  <div class="max-w-4xl mx-auto">
+    <div class="hero min-h-[60vh] bg-base-200 rounded-lg">
+      <div class="hero-content flex-col items-start text-left">
+        <div class="max-w-md">
+          <%= case @result do %>
+            <% :success -> %>
+              <h1 class="text-3xl font-bold">
+                {gettext("Thank you")}
+              </h1>
+              <p class="py-4 text-base-content/80">
+                {gettext("Thank you, we have received your request.")}
+              </p>
+              <p class="text-sm text-base-content/70">
+                {gettext("You will receive an email once your application has been reviewed.")}
+              </p>
+              <a href={~p"/join"} class="btn btn-primary mt-4">
+                {gettext("Back to join form")}
+              </a>
+            <% :expired -> %>
+              <h1 class="text-3xl font-bold">
+                {gettext("Link expired")}
+              </h1>
+              <p class="py-4 text-base-content/80">
+                {gettext("This link has expired. Please submit the form again.")}
+              </p>
+              <a href={~p"/join"} class="btn btn-primary mt-4">
+                {gettext("Submit new request")}
+              </a>
+            <% :invalid -> %>
+              <h1 class="text-3xl font-bold text-error">
+                {gettext("Invalid or expired link")}
+              </h1>
+              <p class="py-4 text-base-content/80">
+                {gettext("Invalid or expired link.")}
+              </p>
+              <a href={~p"/join"} class="btn btn-primary mt-4">
+                {gettext("Go to join form")}
+              </a>
+          <% end %>
+        </div>
+      </div>
+    </div>
+  </div>
+</main>