Fix id based sqlite query

[dcadenas]

Currently, ID-based queries in SQLite are failing. For example, the command:

nak req -i $(nak req -k 1 -l 1 wss://nostr.8777.ch | jq -r '.id') wss://nostr.8777.ch

returns nothing.

This small PR addresses the issue by encoding the ID as a hex value in the same manner as it's done for authors.

Thank you for maintaining this project, and feel free to adjust this as needed!