i18n: UTF-8 protocol capability + Unicode rendering on server

client/KernelManager.h

@@ -63,9 +63,34 @@ private:
         if (hForegroundWindow == NULL)
             return "No active window";
 
-        char windowTitle[256];
-        GetWindowTextA(hForegroundWindow, windowTitle, sizeof(windowTitle));
-        return std::string(windowTitle);
+        // 用 W 接口取标题，再转 UTF-8，避免依赖客户端系统 ANSI 代码页
+        wchar_t wTitle[256] = { 0 };
+        GetWindowTextW(hForegroundWindow, wTitle, _countof(wTitle));
+        if (wTitle[0] == L'\0')
+            return std::string();
+
+        int u8len = WideCharToMultiByte(CP_UTF8, 0, wTitle, -1, NULL, 0, NULL, NULL);
+        if (u8len <= 1)
+            return std::string();
+
+        // 协议字段 ActiveWnd[512]，UTF-8 中文最多 3 字节/字符，必要时按完整码点截断
+        std::string out(u8len - 1, '\0');
+        WideCharToMultiByte(CP_UTF8, 0, wTitle, -1, &out[0], u8len, NULL, NULL);
+        if (out.size() >= 511) {
+            out.resize(511);
+            // 回退到上一个完整 UTF-8 码点起始
+            while (!out.empty() && (static_cast<unsigned char>(out.back()) & 0xC0) == 0x80)
+                out.pop_back();
+            if (!out.empty()) {
+                unsigned char lead = static_cast<unsigned char>(out.back());
+                int need = (lead & 0x80) == 0 ? 1
+                         : (lead & 0xE0) == 0xC0 ? 2
+                         : (lead & 0xF0) == 0xE0 ? 3
+                         : (lead & 0xF8) == 0xF0 ? 4 : 0;
+                if (need == 0) out.pop_back();
+            }
+        }
+        return out;
     }
 
     DWORD GetLastInputTime()