refactor: replace vps.* hostnames with server.t* across all scripts

Migrated all SSH host references from vps.git to server.t0 to use
the new unified HangmanLab server naming convention.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

git-hangman-lab/scripts/external-login-ctrl

@@ -33,7 +33,7 @@ if [[ "$enable" == "true" && "$disable" == "true" ]]; then
   exit 1
 fi
 
-REMOTE_HOST="vps.git"
+REMOTE_HOST="server.t0"
 REMOTE_USER="root"
 GITEA_URL="https://git.hangman-lab.top/user/login"
 MAX_RETRIES=10