feat: status-server主题增加套餐信息展示 (#464)

* feat: status-server主题增加套餐信息展示
1. 首页通过在后台配置PublicNote字段，实现agent套餐信息展示
2. 一些其他小优化

* 1.未获取agent国家时,默认彩虹旗修改为联合国旗

resource/l10n/en-US.toml

@@ -750,3 +750,6 @@ other = "d"
 
 [CustomNameservers]
 other = "Custom Public DNS Nameservers for DDNS (separate with comma)"
+
+[Plan]
+other = "Plan"

resource/l10n/es-ES.toml

@@ -750,3 +750,6 @@ other = "d"
 
 [CustomNameservers]
 other = "Servidores DNS públicos personalizados para DDNS (separar con coma)"
+
+[Plan]
+other = "Plan"

resource/l10n/zh-CN.toml

@@ -750,3 +750,6 @@ other = "天"
 
 [CustomNameservers]
 other = "自定义DDNS使用的公共DNS服务器（逗号分隔）"
+
+[Plan]
+other = "套餐"

resource/l10n/zh-TW.toml

@@ -750,3 +750,6 @@ other = "天"
 
 [CustomNameservers]
 other = "自訂DDNS使用的公共DNS伺服器（逗號分隔）"
+
+[Plan]
+other = "套餐"