Add database backups and automatic restore

Daemon job "backup" (online copy, quick_check, rotation), restore of the
newest valid copy when the database cannot be opened, change journal reset
after restore, last_restore in /health, docs and tests.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

api_server.py

@@ -52,7 +52,7 @@ class CollectRequest(BaseModel):
 
 
 class ScheduleUpdate(BaseModel):
-    type: Literal["asn", "fqdn"]
+    type: Literal["asn", "fqdn", "backup"]
     cron: str
 
     model_config = {"json_schema_extra": {"example": {"type": "asn", "cron": "*/10 * * * *"}}}
@@ -211,6 +211,11 @@ def health():
     with db.session() as conn:
         counts = {"cidrs": db.count_values(conn, "asn"), "fqdn_ips": db.count_values(conn, "fqdn")}
 
+    try:
+        last_restore = load_json(cc.RESTORE_FILE, None)  # след автовосстановления базы из копии
+    except StorageError:
+        last_restore = None
+
     healthy = alive and not any(j.get("last_error") for j in jobs.values())
     return {
         "status": "ok" if healthy else "degraded",
@@ -218,6 +223,7 @@ def health():
         "collector_updated_at": updated_at,
         "jobs": jobs,
         "counts": counts,
+        "last_restore": last_restore,
     }