FIX: CLI bug fixes and minor updates

[jsong468]

Description

This PR makes minor updates to improve the CLI experience, including the following:

• Refactored _cli_args.py to introduce an _ArgSpec dataclass that is used to describe each CLI flag (e.g. initializers, memory-labels, etc.) and how it should be collected and validated. These _ArgSpec objects are passed into a generic helper called _parse_shell_arguments which parses each of the arguments according to their specifications (i.e., flag string, result key for the dictionary, whether or not it takes multiple values as args, and parser for validating/normalizing the user inputted values). This method is called within each of the specific per-command argument parsing methods according to the list of specs associated with that command. This ensures that each argument owns its own validation (each command does not need to know how to parse the arg) and lets us centralize code that was repeated and is extensible for future commands.
• Enable --initializers and --initialization_scripts args in pyrit_shell when calling list-targets
• Enable --initialization_scripts arg in pyrit_scan when calling list_targets
• Raises error when unknown args are provided to a command that does not accept args (e.g. list-scenarios)
• Fixes bug where help command did not work properly for hyphenated commands such as list-targets or list-initializers
• Deletes misc. unused code such as unused param initializer_names in list_targets_async
• Addresses the bug where in pyrit_shell, when do_run and do_list_targets (with args) create a per-command FrontendCore, they didn't propagate the shell's startup config (config_file, database, env_files). The new context fell back to the default ~/.pyrit/.pyrit_conf, silently losing any custom config passed via --config-file. This caused per-command contexts to use the wrong database type, env files, operator/operation labels, etc. The fix implemented here is to use a with_overrides() method in FrontendCore to create a derived instance without re-loading and reading config files (using object.__new()__ and not __init__), copy over inherited state (which includes _database, _env_files, _operator, _operation, _config) as the base, applies overrides on the per-command fields (initializer_names, initialization_scripts, log_level), and shares the parent's registries. Both do_run and do_list_targets now use this method. Also sets _silent_reinit = True on the derived context to suppress redundant initialization output.
• Removes ._config attribute in FrontEndCore since it is dead state and not referenced anywhere beyond being set.

Tests and Documentation

Unit tests added to ensure behavior of all of the above changes

[Copilot]

Pull request overview

This PR improves the PyRIT CLI/shell UX by expanding list-targets support (initializers + initialization scripts), tightening argument validation for no-arg commands, fixing help lookup for hyphenated commands, and cleaning up unused CLI plumbing.

Changes:

• Add list-targets option parsing in pyrit_shell and enable --initialization-scripts handling in pyrit_scan.
• Reject unexpected args for commands that should not take arguments and normalize hyphenated command names for help.
• Refactor target listing initialization flow (remove unused initializer_names param) and add unit tests covering new behaviors.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
pyrit/cli/pyrit_shell.py	Adds arg rejection for no-arg commands; adds option parsing + context override for list-targets; fixes help for hyphenated commands.
pyrit/cli/pyrit_scan.py	Resolves --initialization-scripts for --list-targets and surfaces missing-script errors.
pyrit/cli/frontend_core.py	Removes unused initializer_names param from list_targets_async and supports initialization-scripts-only population.
pyrit/cli/_cli_args.py	Introduces parse_list_targets_arguments for shell-mode parsing.
pyrit/cli/_banner.py	Updates banner text to reflect list-targets [opts].
tests/unit/cli/test_pyrit_shell.py	Adds coverage for arg rejection, list-targets option flow, and hyphenated help.
tests/unit/cli/test_pyrit_scan.py	Adds coverage for --list-targets with initializers and initialization scripts.
tests/unit/cli/test_frontend_core.py	Adds coverage for parse_list_targets_arguments and scripts-only target listing initialization.