feat: add filestore for filelogreceivers to store offsets

[gmlexx]

Close #537

On restart it's reading the fileoffset from storage to resume reading logs.

2025-09-23T10:03:44.428Z        info    fileconsumer/file.go:62 Resuming from previously known offset(s). 'start_at' setting is not applicable. {"name": "filelog//receiver_creator{endpoint=\"172.18.0.3\"}/k8s_observer/9beeea60-fd96-4ec5-9180-a2880ffc0584/kube-proxy", "component": "fileconsumer"}