[电大老baby (HhH666-ux)]

Description

SearchReplaceConverter.__init__ validated the compiled regex pattern but not the templates in replace. Invalid templates (bad escapes, references to missing groups, unknown named groups) only failed later inside convert_async with an unhandled re.error or IndexError.

• Validate every template in replace against the compiled pattern during construction and raise a descriptive ValueError.
• Add regression tests for an invalid escape, a missing group reference, and an unknown named group.

Fixes #4076

[Copilot]

🟢 Approval recommended

No active review issues are reported for the change that validates replacement templates during converter initialization.

No open issues 🎉

What changed in this PR

This PR addresses #4076 by moving replacement-template validation into SearchReplaceConverter construction, so invalid configurations raise a descriptive ValueError before conversion runs.

Changes:

• Validate every replacement template against the compiled regex during initialization.
• Document the new validation and add tests for invalid escapes, missing groups, unknown named groups, and a valid named-group reference.

File	Description
tests/​unit/​converter/​test_search_replace_converter.py	Adds invalid-template regression tests and a valid-template acceptance test.
pyrit/​converter/​search_replace_converter.py	Validates replacement templates during construction and documents the resulting errors.

_{Review effort: Balanced}