Initial WatchLink scaffold

src/app/login/page.tsx

@@ -0,0 +1,31 @@
+import Link from "next/link";
+import { loginUser } from "@/lib/user-actions";
+
+export default function LoginPage() {
+  return (
+    <main className="auth-page">
+      <section className="auth-card">
+        <div className="title-block" style={{ marginBottom: 18 }}>
+          <h1>Login</h1>
+          <p>Enter WatchLink with your username and password.</p>
+        </div>
+        <form className="form" action={loginUser}>
+          <label>
+            Username
+            <input className="input" name="username" autoComplete="username" required />
+          </label>
+          <label>
+            Password
+            <input className="input" name="password" type="password" autoComplete="current-password" required />
+          </label>
+          <button className="button primary" type="submit">
+            Login
+          </button>
+          <Link className="button" href="/register">
+            Create account
+          </Link>
+        </form>
+      </section>
+    </main>
+  );
+}