FIX: Coerce typed scenario parameters in scan CLI

[biefan]

Description

• Fix pyrit_scan handling of scenario-declared CLI parameters so invalid boolean tokens are rejected instead of silently becoming false.
• Coerce list parameter elements, such as list[int], before sending scenario_params to the backend.
• Coerce typed choices before argparse validation so numeric choices are compared using the correct type.

Tests and Documentation

• uv run -m pytest tests/unit/cli/test_pyrit_scan.py tests/unit/cli/test_pyrit_shell.py -q
• uv run -m pytest tests/unit/cli -q
• uv run -m ty check pyrit/cli/pyrit_scan.py tests/unit/cli/test_pyrit_scan.py
• uv run pre-commit run --files pyrit/cli/pyrit_scan.py tests/unit/cli/test_pyrit_scan.py

Documentation changes are not needed for this CLI bug fix.