Revert "default to gamma (#3362)" (#3364)

This reverts commit cf9ce51.

Author: evanliu048

crates/chat-cli/src/auth/portal.rs

@@ -36,7 +36,7 @@ use crate::auth::social::{
 use crate::database::Database;
 use crate::util::system_info::is_mwinit_available;
 
-const DEFAULT_AUTH_PORTAL_URL: &str = "https://gamma.app.kiro.dev";
+const DEFAULT_AUTH_PORTAL_URL: &str = "https://app.kiro.dev";
 const DEFAULT_AUTHORIZATION_TIMEOUT: Duration = Duration::from_secs(600);
 
 #[derive(Debug, Clone)]

crates/chat-cli/src/cli/chat/cli/subscribe.rs

@@ -22,7 +22,7 @@ use crate::os::Os;
 use crate::theme::StyledText;
 use crate::util::system_info::is_remote;
 
-const DEFAULT_SUBSCRIPTION_DOMAIN: &str = "gamma.app.kiro.dev";
+const DEFAULT_SUBSCRIPTION_DOMAIN: &str = "app.kiro.dev";
 
 fn get_subscription_url() -> String {
     let domain = env::var("KIRO_SUBSCRIPTION_DOMAIN").unwrap_or_else(|_| DEFAULT_SUBSCRIPTION_DOMAIN.to_string());