feat: add access log functionality and related components

- Introduced NodeAccessLog model and corresponding database migrations.
- Implemented access log retrieval in the service layer.
- Created API endpoint for accessing logs with appropriate security measures.
- Developed frontend components for displaying access logs, including filtering and summary statistics.
- Updated observability buffer to include access logs and ensure proper merging and retention.
- Enhanced traffic report and observability tests to validate new access log features.
- Updated documentation to reflect changes in access log handling and data retention policies.

atsf_server/service/access_log.go

@@ -0,0 +1,55 @@
+package service
+
+import (
+	"atsflare/model"
+	"strings"
+	"time"
+)
+
+const accessLogListLimit = 500
+
+type AccessLogView struct {
+	ID         uint      `json:"id"`
+	NodeID     string    `json:"node_id"`
+	NodeName   string    `json:"node_name"`
+	LoggedAt   time.Time `json:"logged_at"`
+	RemoteAddr string    `json:"remote_addr"`
+	Host       string    `json:"host"`
+	Path       string    `json:"path"`
+	StatusCode int       `json:"status_code"`
+}
+
+func ListAccessLogs(nodeID string) ([]AccessLogView, error) {
+	logs, err := model.ListNodeAccessLogs(strings.TrimSpace(nodeID), time.Now().Add(-nodeAccessLogRetentionWindow), accessLogListLimit)
+	if err != nil {
+		return nil, err
+	}
+	nodes, err := model.ListNodes()
+	if err != nil {
+		return nil, err
+	}
+	nodeNames := make(map[string]string, len(nodes))
+	for _, node := range nodes {
+		if node == nil {
+			continue
+		}
+		nodeNames[node.NodeID] = node.Name
+	}
+	views := make([]AccessLogView, 0, len(logs))
+	for _, item := range logs {
+		if item == nil {
+			continue
+		}
+		views = append(views, AccessLogView{
+			ID:         item.ID,
+			NodeID:     item.NodeID,
+			NodeName:   nodeNames[item.NodeID],
+			LoggedAt:   item.LoggedAt,
+			RemoteAddr: item.RemoteAddr,
+			Host:       item.Host,
+			Path:       item.Path,
+			StatusCode: item.StatusCode,
+		})
+	}
+	return views, nil
+}