Add forgot-password and reset-password flow

Users can now request a password reset link via email. Better Auth
sendResetPassword callback sends a branded email via Resend. Login
page shows success notice after password is set.

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

src/app/(auth)/forgot-password/page.tsx

@@ -0,0 +1,23 @@
+import { getSetting } from "@/lib/settings";
+import { ForgotPasswordForm } from "./forgot-password-form";
+
+export default async function ForgotPasswordPage() {
+  const schoolName = await getSetting("schoolName");
+  return (
+    <div className="min-h-screen flex items-center justify-center" style={{ backgroundColor: "var(--background)" }}>
+      <div className="w-full max-w-sm">
+        <div className="text-center mb-8">
+          <h1 className="text-2xl font-bold tracking-wide" style={{ color: "var(--foreground)" }}>
+            {schoolName}
+          </h1>
+          <p className="mt-1 text-sm uppercase tracking-widest" style={{ color: "var(--muted-foreground)", fontSize: "0.65rem" }}>
+            Образовательная платформа
+          </p>
+        </div>
+        <div className="card-aubade p-8">
+          <ForgotPasswordForm />
+        </div>
+      </div>
+    </div>
+  );
+}