♻️ refactor: Login and Registration component Improvement (#2716)

* ♻️ refactor: Login form improvement

* display error message when API is down
* add loading animation to Login form while fetching data
* optimize startupConfig to fetch data only on initial render to prevent unnecessary API calls

* 🚑 fix: clear authentication error messages on successful login

* ♻️ refactor: componentize duplicate codes on registration and login screens

* chore: update types

* refactor: layout rendering order

* refactor: startup title fix

* refactor: reset/request-reset-password under new AuthLayout

* ci: fix Login.spec.ts

* ci: fix registration.spec.tsx

---------

Co-authored-by: Danny Avila <danny@librechat.ai>

client/src/components/Auth/BlinkAnimation.tsx

@@ -0,0 +1,29 @@
+export const BlinkAnimation = ({
+  active,
+  children,
+}: {
+  active: boolean;
+  children: React.ReactNode;
+}) => {
+  const style = `
+  @keyframes blink-animation {
+    0%,
+    100% {
+      opacity: 1;
+    }
+    50% {
+      opacity: 0;
+    }
+  }`;
+
+  if (!active) {
+    return <>{children}</>;
+  }
+
+  return (
+    <>
+      <style>{style}</style>
+      <div style={{ animation: 'blink-animation 3s infinite' }}>{children}</div>
+    </>
+  );
+};