Include panel member tokens in the chain cost badge

Panel member token usage was tracked but discarded, so the cost badge only
ever showed the worker's tokens — misleading for MoA where the real cost is
roughly rounds x agents. Collect each member's usage and add it to the badge.

Each member fills its own TokenUsage in parallel (Anthropic loop via the
existing memberUsage, CLI via the now-captured CliChatResult return value;
OpenAI members stay null, nachruestbar). RunPanel sums them after the
Task.WhenAll barrier — single-threaded, so no lock or Interlocked needed —
across all MoA rounds and emits a panel_usage SSE event before panel_done.
The frontend adds those tokens onto the worker totals in the done handler so
the badge reflects the full chain cost.

- SseHelper: add TokenUsage.Add()
- AnthropicService.Panel.cs: PanelMemberResult.Usage, accumulate per round
  after the barrier, emit panel_usage; RunPanelMemberViaCli returns usage
- chat.js: _panelUsage state, panel_usage case, add to worker tokens on done,
  reset on stream start
- TODO.md: check off the member-token item

v1 limit: live badge only — FinalizeChain still persists worker tokens, so a
reload shows worker-only cost.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Services/AnthropicService.Panel.cs

@@ -35,6 +35,7 @@ public partial class AnthropicService
         public string Name { get; set; }
         public string Model { get; set; }
         public string Text { get; set; }
+        public TokenUsage Usage { get; set; } // Token-Verbrauch dieses Members (für die Chain-Kosten)
     }
 
     /// <summary>
@@ -67,6 +68,23 @@ public partial class AnthropicService
         var mode = layers > 1 ? "moa" : "fusion";
         await SseHelper.TryWriteSse(response, "panel_start", new { members = panel.Count, mode, layers }, sseCt, sseGate);
 
+        // Gesamt-Token aller Member über ALLE Runden. Jeder Member sammelt seine eigene Usage
+        // (result.Usage); summiert wird erst NACH der Task.WhenAll-Barrier → kein Lock nötig.
+        // Vor jedem panel_done als panel_usage-Event ans Frontend → addiert auf die Worker-Tokens.
+        var panelUsage = new TokenUsage();
+        async Task SendPanelUsage()
+        {
+            if (panelUsage.InputTokens == 0 && panelUsage.OutputTokens == 0
+                && panelUsage.CacheReadTokens == 0 && panelUsage.CacheCreationTokens == 0) return;
+            await SseHelper.TryWriteSse(response, "panel_usage", new
+            {
+                inputTokens = panelUsage.InputTokens,
+                outputTokens = panelUsage.OutputTokens,
+                cacheCreationTokens = panelUsage.CacheCreationTokens,
+                cacheReadTokens = panelUsage.CacheReadTokens
+            }, sseCt, sseGate);
+        }
+
         // MoA: mehrere Proposer-Runden. Runde k>1 bekommt <previous_layer_responses> und verfeinert.
         // Fusion = layers==1 (keine Vorrunde). prev füttert die nächste Runde bzw. die finale Synthese.
         List<PanelMemberResult> prev = null;
@@ -93,6 +111,12 @@ public partial class AnthropicService
             }
 
             var results = await Task.WhenAll(tasks);
+
+            // Nach der Barrier (single-threaded): Token ALLER Member dieser Runde aufsummieren –
+            // auch von Membern ohne verwertbaren Text (sie haben trotzdem Tokens verbraucht).
+            foreach (var r in results)
+                if (r?.Usage != null) panelUsage.Add(r.Usage);
+
             var ordered = results
                 .Where(r => r != null && !string.IsNullOrWhiteSpace(r.Text))
                 .OrderBy(r => r.Index)
@@ -103,6 +127,8 @@ public partial class AnthropicService
             if (ordered.Count == 0)
             {
                 // Keine verwertbaren Antworten in dieser Runde → ohne Synthese weiter.
+                // Trotzdem die bisher verbrauchten Member-Tokens melden (ehrliche Kosten).
+                await SendPanelUsage();
                 await SseHelper.TryWriteSse(response, "panel_done", new { synthesizing = false, members = 0 }, sseCt, sseGate);
                 return 0;
             }
@@ -130,6 +156,7 @@ public partial class AnthropicService
 
         MergePanelIntoLastUserText(workerMessages, sb.ToString());
 
+        await SendPanelUsage();
         await SseHelper.TryWriteSse(response, "panel_done", new { synthesizing = true, members = prev.Count }, sseCt, sseGate);
         return prev.Count;
     }
@@ -163,6 +190,7 @@ public partial class AnthropicService
         var memberMessages = CloneForMember(workerMessages, previousLayerBlock);
         string text;
         List<object> segments = null; // interleavtes Transkript (Text + Tools) für die Reload-Persistenz
+        TokenUsage memberUsage = null; // Token-Verbrauch dieses Members (null = nicht verfügbar, z.B. OpenAI)
         try
         {
             if (!string.IsNullOrEmpty(member.Provider) && _openAiService != null)
@@ -176,15 +204,15 @@ public partial class AnthropicService
             {
                 // Kein API-Key → CLI-Member, read-only (Plan-Modus: nur Read/Glob/Grep).
                 // Streamt LIVE (Token + Tool-Uses) über panel_member_*-Events und liefert das Transkript.
-                var (t, segs) = await RunPanelMemberViaCli(response, member, memberMessages, index, sseGate, workCt, sseCt);
-                text = t; segments = segs;
+                var (t, segs, u) = await RunPanelMemberViaCli(response, member, memberMessages, index, sseGate, workCt, sseCt);
+                text = t; segments = segs; memberUsage = u;
             }
             else
             {
                 // Anthropic-API-Member: read-only (PlanMode) + NICHT persistieren (Caller persistiert einmal).
                 // Live-Streaming über den Loop: pro Tool-Runde panel_member_text / panel_member_tool.
                 // TranscriptSink sammelt Text-/Tool-Segmente für die Reload-Persistenz.
-                var memberUsage = new TokenUsage();
+                memberUsage = new TokenUsage();
                 segments = new List<object>();
                 var (t, _) = await RunNonStreamingToolLoop(
                     member.ModelId, member.SystemPrompt,
@@ -239,7 +267,7 @@ public partial class AnthropicService
         await SseHelper.TryWriteSse(response, "panel_member_done",
             new { index, name, model = member.ModelId, text }, sseCt, sseGate);
 
-        return new PanelMemberResult { Index = index, Name = name, Model = member.ModelId, Text = text };
+        return new PanelMemberResult { Index = index, Name = name, Model = member.ModelId, Text = text, Usage = memberUsage };
     }
 
     /// <summary>
@@ -250,7 +278,7 @@ public partial class AnthropicService
     /// laufen durch den geteilten <paramref name="sseGate"/> (parallele Member → sonst
     /// vermischen sich die Frames). Persistiert nichts – der Caller speichert eine Proposal-Message.
     /// </summary>
-    private async Task<(string text, List<object> segments)> RunPanelMemberViaCli(
+    private async Task<(string text, List<object> segments, TokenUsage usage)> RunPanelMemberViaCli(
         HttpResponse response,
         SubAgentContext member,
         List<object> memberMessages,
@@ -259,7 +287,7 @@ public partial class AnthropicService
         CancellationToken workCt,
         CancellationToken sseCt)
     {
-        if (_cliService == null || !_cliService.IsAvailable) return ("", new List<object>());
+        if (_cliService == null || !_cliService.IsAvailable) return ("", new List<object>(), null);
 
         var systemText = ExtractSystemPromptText(member.SystemPrompt);
         var prompt = ExtractLastUserText(memberMessages) ?? "";
@@ -292,9 +320,10 @@ public partial class AnthropicService
         // (content_block_stop) vollständig – ToolStart/ToolResult tragen ihn nicht.
         var toolNames = new Dictionary<string, string>();   // toolId -> CLI-Name
         var toolInputs = new Dictionary<string, string>();  // toolId -> Input-JSON
+        CliChatResult cliResult = null; // vor dem try, damit die Usage nach dem finally lesbar ist
         try
         {
-            await _cliService.ChatStreamingAsync(
+            cliResult = await _cliService.ChatStreamingAsync(
                 prompt,
                 async evt =>
                 {
@@ -344,7 +373,14 @@ public partial class AnthropicService
             CleanupTempImages(tempImagePaths);
         }
         FlushText(); // restliches Text-Segment am Ende sichern
-        return (fullText.ToString(), segments);
+        var usage = cliResult == null ? null : new TokenUsage
+        {
+            InputTokens = cliResult.InputTokens,
+            OutputTokens = cliResult.OutputTokens,
+            CacheReadTokens = cliResult.CacheReadTokens,
+            CacheCreationTokens = cliResult.CacheCreationTokens
+        };
+        return (fullText.ToString(), segments, usage);
     }
 
     /// <summary>Extrahiert den System-Prompt-Text aus den List&lt;object&gt;-Blöcken eines SubAgentContext.</summary>