fix(adminui): preserve edited alarm fields on Galaxy address re-pick

src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/Uns/TagEditors/TagConfigJson.cs

@@ -43,4 +43,19 @@ public static class TagConfigJson
         if (value is null) { o.Remove(name); return; }
         o[name] = JsonValue.Create(value is Enum e ? e.ToString() : value);
     }
+
+    /// <summary>
+    /// Merges a freshly-picked Galaxy reference (<c>tag_name.AttributeName</c>) into <paramref name="json"/>
+    /// by setting ONLY the canonical PascalCase <c>FullName</c> key — every other key is preserved verbatim.
+    /// This is the Galaxy address re-pick seam: re-picking an address must update the bound attribute WITHOUT
+    /// discarding fields the operator already edited independently of the address — ESPECIALLY a hand-authored
+    /// <c>alarm</c> object (and root history/array intent, scaling, etc.). Null/blank/malformed input starts
+    /// from a bare <c>{"FullName":...}</c> object.
+    /// </summary>
+    public static string SetFullName(string? json, string fullName)
+    {
+        var o = ParseOrNew(json);
+        o["FullName"] = JsonValue.Create(fullName);
+        return Serialize(o);
+    }
 }