🔄🔐 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/Eng.tsx

@@ -71,10 +71,10 @@ export default {
   com_auth_no_account: 'Don\'t have an account?',
   com_auth_sign_up: 'Sign up',
   com_auth_sign_in: 'Sign in',
-  com_auth_google_login: 'Login with Google',
-  com_auth_facebook_login: 'Login with Facebook',
-  com_auth_github_login: 'Login with Github',
-  com_auth_discord_login: 'Login with Discord',
+  com_auth_google_login: 'Continue with Google',
+  com_auth_facebook_login: 'Continue with Facebook',
+  com_auth_github_login: 'Continue with Github',
+  com_auth_discord_login: 'Continue with Discord',
   com_auth_email: 'Email',
   com_auth_email_required: 'Email is required',
   com_auth_email_min_length: 'Email must be at least 6 characters',
@@ -118,6 +118,7 @@ export default {
   com_auth_to_try_again: 'to try again.',
   com_auth_submit_registration: 'Submit registration',
   com_auth_welcome_back: 'Welcome back',
+  com_auth_back_to_login: 'Back to Login',
   com_endpoint_open_menu: 'Open Menu',
   com_endpoint_bing_enable_sydney: 'Enable Sydney',
   com_endpoint_bing_to_enable_sydney: 'To enable Sydney',