refactor(*): 稳定期治理 - 收敛核心架构、错误语义并修复跨项目数据竞态

backend/internal/handler/announcement.go

@@ -2,7 +2,6 @@ package handler
 
 import (
 	"net/http"
-	"strconv"
 	"time"
 
 	"infinite-canvas/backend/internal/service"
@@ -77,8 +76,11 @@ func RegisterAnnouncementRoutes(r *gin.RouterGroup, svc *service.Service) {
 			failService(c, err)
 			return
 		}
-		page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
-		limit, _ := strconv.Atoi(c.DefaultQuery("limit", "20"))
+		page, limit, err := parsePaginationQuery(c, 20)
+		if err != nil {
+			fail(c, http.StatusBadRequest, err)
+			return
+		}
 		announcements, err := svc.AdminAnnouncementPage(user, service.AdminListQuery{Keyword: c.Query("keyword"), Status: c.Query("status"), Page: page, Limit: limit})
 		if err != nil {
 			failService(c, err)