Refactored start_time setting for global requests to be included in the same
mutation batch that starts the actual operation, matching the pattern used for
node operations. This avoids an extra update_topology_state call and ensures
start_time is set atomically with the operation start.
Also updated nodetool tasks documentation to include creation_time field in
example outputs for status, list, and tree commands.
Co-authored-by: Deexie <56607372+Deexie@users.noreply.github.com>
df0a59ba03
