gn0: dispatch CLI actions via registration table

Adding a CLI action previously required editing two case statements
(run_action and run_configured_action). Introduce ACTION_SPECS, a single
'|'-delimited registry (flag|handler|requires_config|validation_fn|
validation_arg) matching the CLI_OPTION_SPEC / STATS_CATEGORIES encoding,
and replace both dispatchers with table lookups via action_spec_field.

- run_action: looks up requires_config; routes non-config actions
  (--version/--init) through run_unconfigured_action (shared
  config/override/force precheck) and the rest through
  run_configured_action.
- run_configured_action: keeps the force-generate guard and config
  load/log, then runs the entry's validation_fn (with optional arg, used
  by --dry-run) and handler via run_configured_action_body.
- Extracted the --clean inline rm body into a clean_dist handler and
  added an action_print_version handler so every action is just a
  registry entry plus named functions.
- Unknown/empty actions have no entry, so dispatch falls through to the
  same usage + exit 1 behavior as the old case "*)" arm.

Adding an action is now one ACTION_SPECS entry plus its handler/
validation functions; neither dispatcher changes (Open/Closed).

Added test_action_dispatch_is_registry_driven proving every parser
action flag has a registry entry, all handlers/validators resolve, and
unknown actions are rejected. All existing action/dispatcher tests pass
unchanged.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

0 files changed, 0 insertions, 0 deletions