弹幕：广播带半显用户名（前两字+***），前端展示前缀

Made-with: Cursor

server/handlers/site_auth.go

@@ -61,6 +61,19 @@ func SiteDanmakuTokenValid(tokenStr string) bool {
 	return ok
 }
 
+// MaskSiteUsernameForDanmaku 弹幕展示半匿名：1 字为「a***」，2 字及以上为前两字 + ***（如 aa***、ab***）
+func MaskSiteUsernameForDanmaku(username string) string {
+	username = strings.TrimSpace(username)
+	if username == "" {
+		return "***"
+	}
+	runes := []rune(username)
+	if len(runes) == 1 {
+		return string(runes[0]) + "***"
+	}
+	return string(runes[:2]) + "***"
+}
+
 type siteRegisterInput struct {
 	Username string `json:"username" binding:"required"`
 	Password string `json:"password" binding:"required"`

server/pkg/weblive/danmaku.go

@@ -28,9 +28,14 @@ func writeDanmakuJSON(ws *websocket.Conn, v any) error {
 	return ws.WriteMessage(websocket.TextMessage, b)
 }
 
-// handleDanmakuWS 弹幕：收 JSON {"text":"..."}；未带有效 token 仅可收广播不可发。广播 {"type":"dm","text","ts"}，不落库
+// handleDanmakuWS 弹幕：收 JSON {"text":"..."}；未带有效 token 仅可收广播不可发。广播 {"type":"dm","text","from","ts"}，不落库
 func handleDanmakuWS(c *gin.Context) {
-	canSend := handlers.SiteDanmakuTokenValid(c.Query("token"))
+	claims, tokenOK := handlers.ParseSiteClaims(c.Query("token"))
+	canSend := tokenOK
+	fromDisplay := "***"
+	if tokenOK && claims != nil {
+		fromDisplay = handlers.MaskSiteUsernameForDanmaku(claims.Username)
+	}
 
 	ws, err := upgrader.Upgrade(c.Writer, c.Request, nil)
 	if err != nil {
@@ -72,6 +77,7 @@ func handleDanmakuWS(c *gin.Context) {
 		out, err := json.Marshal(map[string]interface{}{
 			"type": "dm",
 			"text": text,
+			"from": fromDisplay,
 			"ts":   time.Now().UnixMilli(),
 		})
 		if err != nil {