tools - traffic_ctl, traffic_layout: use ArgParse groups to handle mutually exclusive options.

[brbzull0]

Make sure we express the intentions properly, using mutex groups from ArgParse.
#12621 needs to go in first, I'll leave this as draft till we get the first pr sorted. DONE

traffic_ctl:

Usage: traffic_ctl [OPTIONS] CMD [ARGS ...]

Commands ---------------------- Description -----------------------
drain                           Drain the requests

Options ======================= Default ===== Description =============

Group (drain_mode)
  -N, --no-new-connection                     Wait for new connections down to threshold before starting draining
  -U, --undo                                  Recover server from the drain mode

traffic_layout:

Usage: traffic_layout CMD [OPTIONS]

Commands ---------------------- Description -----------------------
info                            Show the layout as default

Options ======================= Default ===== Description =============
-j, --json                                    Produce output in JSON format (when supported)

Group (display_mode)
  --features                                  Show the compiled features
  --versions                                  Show various library and other versioning information

relates to #12605

[brbzull0]

[approve ci]

[brbzull0]

[approve ci autest 2]

[github-actions]

This pull request has been automatically marked as stale because it has not had recent activity. Marking it stale to flag it for further consideration by the community.

[brbzull0]

[approve ci]

[Copilot]

Pull request overview

This pull request implements mutually exclusive option groups in two command-line tools (traffic_ctl and traffic_layout) using the new ArgParser mutex group feature from PR #12621. The changes ensure that conflicting options are properly validated and documented.

Changes:

• Added mutex group for traffic_layout info command to make --features and --versions mutually exclusive
• Added mutex group for traffic_ctl server drain command to make --no-new-connection and --undo mutually exclusive

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/traffic_layout/traffic_layout.cc	Refactored info command to use mutex group for --features and --versions options, making them mutually exclusive display modes
src/traffic_ctl/traffic_ctl.cc	Refactored server drain command to use mutex group for --no-new-connection and --undo options, making them mutually exclusive drain modes