fix: Thinking indicator respringt nach chat:final durch trailing events

Nach chat:final kommen oft noch agent-Events rein (Core raeumt nach),
die den Thinking-Indicator wieder anspringen liessen.

- Diagnostic: 3s-Settled-Window nach chat:final, agent_activity-Broadcasts
  werden in dem Fenster unterdrueckt (idle kommt weiter durch).
- Bridge: Gleiches Fenster in _emit_activity() — App bekommt keine
  trailing thinking/tool-Events mehr nach dem finalen Antwort.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

diagnostic/server.js

@@ -82,6 +82,12 @@ const browserClients = new Set();
 let pipelineActive = false;
 let pipelineStartTime = 0;
 
+// Nach chat:final kommen oft noch Trailing Agent-Events. Waehrend dieses
+// Fensters unterdruecken wir agent_activity-Broadcasts, damit der
+// Thinking-Indicator nicht wieder anspringt.
+let lastChatFinalAt = 0;
+const SETTLED_WINDOW_MS = 3000;
+
 function plog(message, level) {
   const elapsed = pipelineActive ? `+${Date.now() - pipelineStartTime}ms` : "";
   const entry = { ts: new Date().toISOString(), level: level || "info", source: "pipeline", message: `${elapsed ? `[${elapsed}] ` : ""}${message}` };
@@ -356,17 +362,22 @@ function handleGatewayMessage(msg) {
         broadcast({ type: "chat_delta", delta, payload });
       }
 
+      // Nach chat:final trickeln noch Aufraeum-Events rein — unterdruecken,
+      // damit der Thinking-Indicator nicht wieder anspringt.
+      const settled = lastChatFinalAt && (Date.now() - lastChatFinalAt) < SETTLED_WINDOW_MS;
+
       // Tool-Nutzung erkennen und broadcasten
       if (stream === "tool_use" || data.type === "tool_use") {
         const toolName = data.name || data.tool || payload.tool || "";
-        if (toolName) {
+        if (toolName && !settled) {
           broadcast({ type: "agent_activity", activity: "tool", tool: toolName, data });
           log("info", "gateway", `Tool: ${toolName}`);
         }
       }
 
-      // Genereller Activity-Heartbeat (ARIA denkt)
-      broadcast({ type: "agent_activity", activity: stream || "thinking" });
+      if (!settled) {
+        broadcast({ type: "agent_activity", activity: stream || "thinking" });
+      }
       updateAgentActivity();
       return;
     }
@@ -381,6 +392,7 @@ function handleGatewayMessage(msg) {
         if (runId && seenFinalRuns.has(runId)) return; // Duplikat
         if (runId) { seenFinalRuns.add(runId); setTimeout(() => seenFinalRuns.delete(runId), 60000); }
         log("info", "gateway", `ANTWORT: "${text.slice(0, 200)}"`);
+        lastChatFinalAt = Date.now();
         if (pipelineActive) pipelineEnd(true, `"${text.slice(0, 120)}"`);
         broadcast({ type: "chat_final", text, payload });
         broadcast({ type: "agent_activity", activity: "idle" });
@@ -424,6 +436,7 @@ function handleGatewayMessage(msg) {
       if (runId) { seenFinalRuns.add(runId); setTimeout(() => seenFinalRuns.delete(runId), 60000); }
       const text = extractChatText(payload) || payload.text || "";
       log("info", "gateway", `ANTWORT: "${text.slice(0, 200)}"`);
+      lastChatFinalAt = Date.now();
       if (pipelineActive) pipelineEnd(true, `"${text.slice(0, 120)}"`);
       else broadcast({ type: "agent_activity", activity: "idle" });
       broadcast({ type: "chat_final", text, payload });