fix(nodes): locate agents behind a proxy and retry missing countries [CI]

backend/src/MoShiro.Backend.Api/Common/ClientAddress.cs

@@ -11,7 +11,7 @@ namespace MoShiro.Backend.Api;
 /// 且从右往左跳过所有可信代理，取第一个不可信的地址（客户端自己伪造的在最左边，不会被采信）。
 /// 没配置就一律用套接字地址：宁可限流和审计里是代理的地址，也不让客户端自己报地址。
 /// </summary>
-public sealed class ClientAddressResolver
+public sealed class ClientAddressResolver : Fleet.Server.IClientAddressSource
 {
     private readonly IPNetwork[] _trusted;
     private readonly string _header;
@@ -43,9 +43,13 @@ public sealed class ClientAddressResolver
         return _trusted.Any(n => n.Contains(normalized));
     }
 
-    public string Resolve(HttpContext http)
+    string? Fleet.Server.IClientAddressSource.Resolve(IPAddress? socket, Func<string, IEnumerable<string>> header) => Resolve(socket, header);
+
+    public string Resolve(HttpContext http) =>
+        Resolve(http.Connection.RemoteIpAddress, name => http.Request.Headers[name].Select(v => v ?? ""));
+
+    private string Resolve(IPAddress? remote, Func<string, IEnumerable<string>> headers)
     {
-        IPAddress? remote = http.Connection.RemoteIpAddress;
         if (remote is null)
         {
             return "unknown";
@@ -56,7 +60,7 @@ public sealed class ClientAddressResolver
             return remote.ToString();
         }
 
-        string[] chain = [.. http.Request.Headers[_header].SelectMany(v => (v ?? "").Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))];
+        string[] chain = [.. headers(_header).SelectMany(v => (v ?? "").Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))];
         for (int i = chain.Length - 1; i >= 0; i--)
         {
             if (!IPAddress.TryParse(chain[i], out IPAddress? hop))