优化分页和筛选功能：实现服务端分页和筛选，修复总数不匹配问题

- 优化设备管理、版本管理、用户管理、在线实例、公告管理页面的分页功能
- 后端添加筛选参数支持（application_id, status, type, search等）
- 前端移除冗余的前端筛选逻辑，改为服务端筛选
- 修复分页总数与筛选数据不匹配的问题
- 优化云端变量记录页面的时间筛选和搜索功能
- 修复DateTimePicker组件关闭后不自动更新的问题

backend/internal/router/admin/announcements.go

@@ -1,4 +1,4 @@
-package admin
+package admin
 
 import (
 	"fmt"
@@ -28,6 +28,10 @@ func handleGetAllAnnouncements(c *gin.Context) {
 
 	page := c.DefaultQuery("page", "1")
 	pageSize := c.DefaultQuery("page_size", "20")
+	applicationIDFilter := c.Query("application_id")
+	typeFilter := c.Query("type")
+	statusFilter := c.Query("status")
+	searchFilter := c.Query("search")
 
 	var total int64
 
@@ -59,7 +63,36 @@ func handleGetAllAnnouncements(c *gin.Context) {
 
 	log.Printf("[DEBUG] appNameMap: %v\n", appNameMap)
 
-	database.DB.Model(&model.Announcement{}).Where("application_id IN ?", appIDs).Count(&total)
+	countQuery := database.DB.Model(&model.Announcement{}).Where("application_id IN ?", appIDs)
+	if applicationIDFilter != "" {
+		countQuery = countQuery.Where("application_id = ?", applicationIDFilter)
+	}
+	if typeFilter != "" {
+		countQuery = countQuery.Where("type = ?", typeFilter)
+	}
+	if statusFilter != "" {
+		countQuery = countQuery.Where("status = ?", statusFilter)
+	}
+	if searchFilter != "" {
+		searchLower := strings.ToLower(searchFilter)
+		countQuery = countQuery.Where("LOWER(title) LIKE ? OR LOWER(content) LIKE ?", "%"+searchLower+"%", "%"+searchLower+"%")
+	}
+	countQuery.Count(&total)
+
+	query := database.DB.Where("application_id IN ?", appIDs)
+	if applicationIDFilter != "" {
+		query = query.Where("application_id = ?", applicationIDFilter)
+	}
+	if typeFilter != "" {
+		query = query.Where("type = ?", typeFilter)
+	}
+	if statusFilter != "" {
+		query = query.Where("status = ?", statusFilter)
+	}
+	if searchFilter != "" {
+		searchLower := strings.ToLower(searchFilter)
+		query = query.Where("LOWER(title) LIKE ? OR LOWER(content) LIKE ?", "%"+searchLower+"%", "%"+searchLower+"%")
+	}
 
 	var announcements []model.Announcement
 	offset := 0
@@ -72,7 +105,7 @@ func handleGetAllAnnouncements(c *gin.Context) {
 		limit = pageSizeInt
 	}
 
-	if err := database.DB.Where("application_id IN ?", appIDs).Order("is_top DESC, created_at DESC").Limit(limit).Offset(offset).Find(&announcements).Error; err != nil {
+	if err := query.Order("is_top DESC, created_at DESC").Limit(limit).Offset(offset).Find(&announcements).Error; err != nil {
 		response.Error(c, 500, "获取公告列表失败")
 		return
 	}