fix: audit logger stream-based queryLogs

[sigfawn]

This PR prevents memory exhaustion (OOM) when querying large audit logs.

1. Stream-based File Reading

• Problem: The queryLogs method was using fs.readFile to load the entire log file content into memory at once. For large log files (100MB+), this allocated massive strings on the heap, causing OOM crashes or severe GC pauses.
• Fix: Replaced fs.readFile with fs.createReadStream and readline.createInterface. This processes the file line-by-line, maintaining a constant O(1) memory footprint regardless of file size.

Result: Scalable log querying that is safe for production use with large log rotation policies.