fix(llm): strip inline <think> reasoning from Dahl/MiniMax streams; dedupe identical parallel tool calls; hermetic config tests

internal/agent/agent_test.go

@@ -206,3 +206,29 @@ func TestSummarizeNowManual(t *testing.T) {
 		t.Fatalf("%v %v", sm, err)
 	}
 }
+
+func TestDuplicateToolCallsRunOnce(t *testing.T) {
+	st := newStore(t)
+	ss, _ := st.CreateSession(context.Background(), "")
+	n := 0
+	now := func() time.Time { n++; return time.Date(2026, 10, 25, 6, 0, 0, 0, time.UTC) }
+	dup := []llm.ToolCall{{ID: "a", Name: "time_now", Arguments: `{"timezone":"UTC"}`}, {ID: "b", Name: "time_now", Arguments: `{"timezone":"UTC"}`}, {ID: "c", Name: "time_now", Arguments: `{}`}}
+	p := &scripted{resps: []llm.Response{{ToolCalls: dup}, {Content: "ok"}}}
+	a := &Agent{LLM: p, Store: st, Tools: tools.NewRegistry(tools.TimeNow{Now: now}), MaxIterations: 3}
+	if _, err := a.Run(context.Background(), ss.ID, "zeit?", nil); err != nil {
+		t.Fatal(err)
+	}
+	if n != 2 {
+		t.Fatalf("tool executed %d times, want 2", n)
+	}
+	msgs, _ := st.Messages(context.Background(), ss.ID, 0)
+	tools := 0
+	for _, m := range msgs {
+		if m.Role == llm.RoleTool {
+			tools++
+		}
+	}
+	if tools != 3 {
+		t.Fatalf("every call id needs a result, got %d", tools)
+	}
+}