feat(cli): add intent typology listing

[sandeeptv]

Closes #2123.

This replaces #2132, which GitHub closed automatically when the fork branch was renamed from codex/list-intents to feat/list-intents. It is the same reviewed commit, not a duplicate implementation.

What this changes

• adds --list_intents with C, T, M, and S branch grouping
• marks intents that have detector or stub content
• adds verbose markdown output with code, name, description, and content status
• supports --spec inclusion and exclusion filters
• returns a failure status for invalid intent codes and points users to --list_intents
• handles empty filtered results with stable output

I searched open and closed pull requests for #2123 and list_intents immediately before the original submission and found no earlier implementation.

Verification

• python -m pytest tests/cli/test_cli.py tests/cli/test_cli_list_filtering.py tests/cli/test_cli_list_intents.py tests/cas/test_intentservice.py tests/cas/test_intent_run_spec.py -q -k "not test_run_all_active_probes"
  • 53 passed, 1 skipped, 1 deselected
  • the deselected test downloads a model from Hugging Face and cannot run in the offline test environment
• python -m black --config pyproject.toml --check on all changed Python files
• git diff --check
• python -m build --no-isolation
  • built the source distribution and wheel successfully
• verified positive behavior, exclusions, empty results, and invalid-code failure behavior in CLI tests
• supporting generator configuration
  • not applicable
• garak -t <target_type> -n <model_name>
  • not applicable because this change only adds a discovery command

AI assistance disclosure

OpenAI Codex assisted with this contribution. I reviewed every changed line and ran the verification listed above. The commit includes the required DCO sign-off and AI-attribution trailer.