Remove Discord and Google OAuth verification from CMS

- Remove Discord + Google OAuth providers from NextAuth config
- Remove social login buttons (Discord/Google) from login form
- Delete link-discord.ts action and discord-verify-form.tsx component
- Simplify verify page to email-only verification flow
- Remove connections settings page and its link from settings
- Clean env.ts, .env, .env.example of Discord/Google client vars
- Remove discordUrl social icon from register, login, and homepage
- Clean translation files: remove continueWithDiscord, continueWithGoogle, connections keys

src/messages/en.json

@@ -862,12 +862,7 @@
 			"securityTitle": "Security",
 			"securitySubtitle": "Two-factor authentication",
 			"securityDescription": "Add a second layer of protection to your account.",
-			"twoFactorLink": "Two-factor authentication",
-			"connectionsTitle": "Connected accounts",
-			"connectionsSubtitle": "Sign in with one click",
-			"connectionsDescription": "Link Discord or Google to your hotel account.",
-			"manageConnections": "Manage connections"
-		},
+			"twoFactorLink": "Two-factor authentication"},
 		"settings2fa": {
 			"backToSettings": "← Settings",
 			"title": "Two-factor authentication",
@@ -889,20 +884,6 @@
 			"enableIntro": "Add a second layer of security with an authenticator app.",
 			"enable": "Enable 2FA"
 		},
-		"connections": {
-			"backToSettings": "← Settings",
-			"title": "Connected accounts",
-			"subtitle": "Link a social account so you can sign in with one click",
-			"matchByEmail": "We match it to your hotel account by e-mail, so use the address on file:",
-			"lookupFailed": "We couldn't read your linked accounts right now. You can still connect below — your status will show once it's available.",
-			"statusUnavailable": "Not available on this hotel.",
-			"statusConnected": "Connected — sign in with this account.",
-			"statusNotConnected": "Not connected.",
-			"connected": "Connected",
-			"connectProvider": "Connect {provider}",
-			"unavailable": "Unavailable",
-			"footerNote": "Connecting takes you to the provider to authorise, then back here. If your social account's e-mail doesn't match a hotel account, you'll be returned to the login screen with a note."
-		},
 		"login": {
 			"title": "Sign in",
 			"subtitle": "Welcome back — log in to enter the hotel.",
@@ -916,8 +897,6 @@
 			"verify": "Verify",
 			"signIn": "Sign in",
 			"or": "or",
-			"continueWithDiscord": "Continue with Discord",
-			"continueWithGoogle": "Continue with Google",
 			"noAccount": "No account?",
 			"createOne": "Create one",
 			"forgotPassword": "Forgot password?",