Feat: Add whitelist action to log-list right-click menu

Adds a "白名单" item after "解除封禁" in the message-log context menu.
It extracts the IP from each selected log entry, asks for confirmation,
then adds it to the shared IPWhitelist singleton — which IOCPServer and
the DLL rate limiter already consult live — so the entry takes effect on
new connections immediately, without a restart. The whitelist is
persisted to settings\IPWhitelist the same way the Network dialog does.

- An IP already in the whitelist is reported as such and skipped.
- An IP in the IP blacklist (banned) is reported as banned and skipped,
  rather than silently removed from the blacklist.
- Menu item, confirmation, and result strings are added to the
  en_US/zh_TW/de_DE language files.

Co-Authored-By: deepseek-v4-pro

server/2015Remote/lang/en_US.ini

@@ -2102,3 +2102,8 @@ TLS
 确定取消选中主机的 TLS 传输吗？（客户端下次启动生效）=Disable TLS transport for the selected host? (takes effect after the client restarts)
 服务端未启用 TLS 证书，无法切换客户端 TLS 传输=Server TLS certificate is not enabled; cannot toggle client TLS transport
 读取服务端 TLS 证书失败，无法下发=Failed to read the server TLS certificate; cannot distribute
+白名单=Whitelist
+确定将选中日志中的 IP 加入白名单吗？=Add the IP from the selected log entries to the whitelist?
+已将 %d 个 IP 加入白名单=Added %d IP(s) to the whitelist
+%d 个 IP 已在白名单中=%d IP(s) already in the whitelist
+%d 个 IP 已封禁，无法加入白名单=%d IP(s) are banned and cannot be added to the whitelist