Fix invalid regex escape warnings

[Mirochill]

Summary:

• Fixes Invalid escape sequence warnings #391.
• Converts the four reported regex patterns in mavisp/modules.py to raw strings.
• Preserves the existing regex behavior while avoiding Python invalid escape sequence warnings.

Validation:

• git diff --check
• Targeted rg check for the reported escaped patterns in mavisp/modules.py

Not run locally: test suite.

[mtiberti]

hi @Mirochill , thanks for your PRs. Look sensible at first sight.

Are you a human or a bot, and are these AI-generated code changes? Same for questions for #461

[Mirochill]

Thanks for asking. Both #461 and #462 were prepared with AI assistance through this GitHub account, not by a project-side bot. The changes were kept limited to the reported issues, and I checked the final diffs for scope and provenance. I did not run local tests; I only did static diff review, and I do not see CI checks published for these branches. If AI-assisted contributions are not acceptable for this project, I can close the PRs.