Function get_next_pending 

pub fn get_next_pending(
    conn: &Connection,
) -> Result<Option<(String, Value)>, Error>

Get the next pending job (highest priority, oldest first). Returns the job ID and its data as a JSON value.

Note: Prefer claim_next_job for executor use — it atomically selects and marks the job as processing in a single transaction, preventing race conditions when multiple executors share a database.