feat(去重逻辑): 增强信号去重机制以区分不同动作

Changes:
* 更新去重键计算逻辑，新增动作字段以区分不同的交易动作（如 REDUCE 和 CLOSE）
* 增加单元测试以验证不同动作在相同价格下的去重行为
* 更新文档以反映去重窗口的变化，确保准确性

internal/subscriber/dedup_test.go

@@ -67,6 +67,31 @@ func TestSignalHashIgnoresUnrelatedFields(t *testing.T) {
 	}
 }
 
+func TestSignalHashDistinguishesAction(t *testing.T) {
+	base := map[string]interface{}{
+		"strategyCode": "BLONG",
+		"symbol":       "SOLUSDT",
+		"period":       "30m",
+		"side":         "SHORT",
+		"price":        101.32,
+	}
+	reduce := cloneFields(base)
+	reduce["action"] = "REDUCE"
+	closeMsg := cloneFields(base)
+	closeMsg["action"] = "CLOSE"
+	if SignalHash("trade-signal", reduce) == SignalHash("trade-signal", closeMsg) {
+		t.Fatal("REDUCE and CLOSE at the same price should hash differently")
+	}
+}
+
+func cloneFields(in map[string]interface{}) map[string]interface{} {
+	out := make(map[string]interface{}, len(in)+1)
+	for k, v := range in {
+		out[k] = v
+	}
+	return out
+}
+
 func TestMemoryDeduperClaimOnce(t *testing.T) {
 	d := NewMemoryDeduper()
 	ok, err := d.Claim(context.Background(), "abc")
@@ -131,6 +156,49 @@ func TestHandleDedupByStrategySymbolPeriodDirectionPrice(t *testing.T) {
 	}
 }
 
+func TestHandleDedupKeepsReduceThenClose(t *testing.T) {
+	dedup := NewMemoryDeduper()
+	var events []string
+	process := func(_ context.Context, req notify.Request) (notify.Result, error) {
+		events = append(events, req.Event)
+		return notify.Result{Matched: true}, nil
+	}
+	lookup := func(context.Context, string) (*model.Source, error) { return enabledSrc(), nil }
+	conv := tradesignal.NewConverter(nil)
+	reduce := []byte(`{
+		"signalId":"local-0f6f4b00e143f8ee:update:1787629790828:0.12",
+		"sourcePosId":"local-0f6f4b00e143f8ee","sourcePosIds":["3340443882114850823"],
+		"strategyCode":"BLONG","symbol":"SOLUSDT","side":"SHORT","action":"REDUCE",
+		"quantity":0.11,"price":101.32,"leverage":20,"period":"30m",
+		"eventTime":"2026-08-25T03:49:51.155Z","addCount":0,"totalPos":0.12,
+		"totalAvgPx":102.64,"posMarginRatio":0.478261,"oldQuantity":0.23,"deltaQuantity":-0.11
+	}`)
+	closeBody := []byte(`{
+		"signalId":"local-0f6f4b00e143f8ee:close:1787629790936:0",
+		"sourcePosId":"local-0f6f4b00e143f8ee","sourcePosIds":["3340443882114850823"],
+		"strategyCode":"BLONG","symbol":"SOLUSDT","side":"SHORT","action":"CLOSE",
+		"quantity":0.12,"price":101.32,"leverage":1,"period":"30m",
+		"eventTime":"2026-08-25T03:49:51.389Z","addCount":0,"totalPos":0,
+		"totalAvgPx":0,"posMarginRatio":1,"oldQuantity":0.12
+	}`)
+	if d := HandleMessage(context.Background(), HandleInput{
+		Body: reduce, SourceName: "trade-signal", MaxRetry: 3, Deduper: dedup,
+	}, conv, lookup, process); d != DispositionAck {
+		t.Fatalf("reduce=%v", d)
+	}
+	if d := HandleMessage(context.Background(), HandleInput{
+		Body: closeBody, SourceName: "trade-signal", MaxRetry: 3, Deduper: dedup,
+	}, conv, lookup, process); d != DispositionAck {
+		t.Fatalf("close=%v", d)
+	}
+	if len(events) != 2 {
+		t.Fatalf("reduce then close should both notify, got %v", events)
+	}
+	if events[0] != "trade.reduce" || events[1] != "trade.close" {
+		t.Fatalf("events=%v", events)
+	}
+}
+
 func TestHandleDedupKeepsDifferentSources(t *testing.T) {
 	dedup := NewMemoryDeduper()
 	var n atomic.Int32