🔄🔐 refactor: auth; style: match OpenAI; feat: custom social login order (#1421)

* refactor(Login & Registration)

* fix(Registration) test errors

* refactor(LoginForm & ResetPassword)

* fix(LoginForm): display 'undefined' when loading page; style(SocialButton): match OpenAI's graphics

* some refactor and style update for social logins

* style: width like OpenAI; feat: custom social login order; refactor: alphabetical socials

* fix(Registration & Login) test

* Update .env.example

* Update .env.example

* Update dotenv.md

* refactor: remove `SOCIAL_LOGIN_ORDER` for `socialLogins` configured from `librechat.yaml`
- initialized by AppService, attached as app.locals property
- rename socialLoginOrder and loginOrder to socialLogins app-wide for consistency
- update types and docs
- initialize config variable as array and not singular string to parse
- bump data-provider to 0.3.9

---------

Co-authored-by: Danny Avila <messagedaniel@protonmail.com>

client/src/localization/languages/It.tsx

@@ -71,10 +71,10 @@ export default {
   com_auth_no_account: 'Non hai un account?',
   com_auth_sign_up: 'Registrati',
   com_auth_sign_in: 'Accedi',
-  com_auth_google_login: 'Accedi con Google',
-  com_auth_facebook_login: 'Accedi con Facebook',
-  com_auth_github_login: 'Accedi con Github',
-  com_auth_discord_login: 'Accedi con Discord',
+  com_auth_google_login: 'Continua con Google',
+  com_auth_facebook_login: 'Continua con Facebook',
+  com_auth_github_login: 'Continua con Github',
+  com_auth_discord_login: 'Continua con Discord',
   com_auth_email: 'Email',
   com_auth_email_required: 'L\'email è obbligatoria',
   com_auth_email_min_length: 'L\'email deve essere lunga almeno 6 caratteri',