Use the real Steam build id for private branches

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

CVRManager.csproj

@@ -9,7 +9,7 @@
     <AssemblyName>CVRManager</AssemblyName>
     <ApplicationIcon>Assets/app.ico</ApplicationIcon>
     <NoWarn>$(NoWarn);CA1416</NoWarn>
-    <Version>1.0.1</Version>
+    <Version>1.0.2</Version>
   </PropertyGroup>
 
   <ItemGroup>

Services/SteamDownloader.cs

@@ -68,12 +68,18 @@ public static class SteamDownloader
             if (priv.Result != EResult.OK) { log($"Steam would not list the files of '{pb.Name}' ({priv.Result})."); continue; }
             var selection = SelectDepots(depots, priv.DepotSection, pb.Name);
             if (selection.Count == 0) continue;
-            list.Add(new BranchInfo(pb.Name, PrivateMarker(selection), true, ""));
+            list.Add(new BranchInfo(pb.Name, PrivateBuildId(priv.DepotSection, pb.Name) ?? PrivateMarker(selection), true, ""));
         }
 
         return list.OrderBy(b => b.Name == "public" ? 0 : 1).ThenBy(b => b.Name).ToList();
     }
 
+    static string? PrivateBuildId(KeyValue? section, string branch)
+    {
+        var id = section?["branches"][branch]["buildid"].Value;
+        return string.IsNullOrEmpty(id) ? null : id;
+    }
+
     static string PrivateMarker(IEnumerable<(uint DepotId, ulong ManifestId)> depots)
     {
         var text = string.Join(";", depots.OrderBy(d => d.DepotId).Select(d => $"{d.DepotId}:{d.ManifestId}"));
@@ -168,7 +174,7 @@ public static class SteamDownloader
             plans.Add(new DepotPlan(depotId, manifestId, keyReply.DepotKey));
         }
         if (plans.Count == 0) throw new InvalidOperationException("Steam listed no downloadable files for this branch.");
-        if (buildId.Length == 0) buildId = PrivateMarker(plans.Select(p => (p.DepotId, p.ManifestId)));
+        if (buildId.Length == 0) buildId = PrivateBuildId(privateDepots, branch) ?? PrivateMarker(plans.Select(p => (p.DepotId, p.ManifestId)));
 
         var statePath = Path.Combine(stateDir, "state.json");
         var state = new InstallState();