Add --no-write-to-file flag for read-only doccmd commands

[adamtheturtle]

Summary

• Add --no-write-to-file flag to doccmd invocations that use read-only tools (shellcheck, mypy, pyright, vulture, pylint, interrogate)
• Tools that write to files (shfmt --write, ruff check --fix, ruff format) are intentionally not changed

Test plan

• Pre-commit hooks pass
• Read-only checks work correctly with the new flag

🤖 Generated with Claude Code