feat: Add authentication templates and actions

app/templates/auth/login/show.html.erb

@@ -0,0 +1,39 @@
+<div class="auth-container">
+  <div class="auth-card">
+    <h1>Login</h1>
+
+    <% if flash[:error] %>
+      <div class="alert alert-error"><%= flash[:error] %></div>
+    <% end %>
+
+    <% if flash[:success] %>
+      <div class="alert alert-success"><%= flash[:success] %></div>
+    <% end %>
+
+    <form action="/auth/login" method="POST">
+      <div class="form-group">
+        <label for="email">Email</label>
+        <input type="email" id="email" name="email" required autocomplete="email">
+      </div>
+
+      <div class="form-group">
+        <label for="password">Password</label>
+        <input type="password" id="password" name="password" required autocomplete="current-password">
+      </div>
+
+      <div class="form-group remember-me">
+        <label>
+          <input type="checkbox" name="remember" value="1">
+          Remember me
+        </label>
+      </div>
+
+      <button type="submit" class="btn btn-primary btn-block">Login</button>
+    </form>
+
+    <div class="auth-links">
+      <p>Don't have an account? <a href="/register">Register here</a></p>
+      <p><a href="/password/reset">Forgot password?</a></p>
+    </div>
+  </div>
+</div>