chore: add clickhouse as db for logs on agent and search

backend/internal/storage/log_entry.go

@@ -0,0 +1,11 @@
+package storage
+
+import "time"
+
+type LogEntry struct {
+	Timestamp time.Time `ch:"timestamp"`
+	Level     string    `ch:"level"`
+	Service   string    `ch:"service"`
+	Agent     string    `ch:"agent"`
+	Message   string    `ch:"message"`
+}