Clarify Python line length guidance for contributors and AI agents

Summary The contributor guidance in AGENTS.md asks Python contributors to follow a 100-character line length, while the executable tooling configuration in pyproject.toml sets both Ruff and isort to 120 characters. This appears to be a documentation clarification issue rather than a confirmed bug.

Current guidance AGENTS.md says:

• AGENTS.md:24 - "Use Python 3.11+ features and type hints"
• AGENTS.md:25 - "Follow PEP 8 with a line length of 100 characters"

Tooling configuration pyproject.toml configures:

• pyproject.toml:333 - [tool.ruff] line-length = 120
• pyproject.toml:346 - [tool.isort] line_length = 120

Why clarification would help The current guidance can leave human contributors unsure whether they should manually wrap Python code at 100 characters or follow the 120-character limit used by the formatter/import sorter. It can also affect AI coding agents that read AGENTS.md as repo-specific instructions and may format changes differently from the configured tools.

Possible resolutions Could maintainers confirm the intended policy?

• Is 100 characters the preferred human style, with 120 characters as the enforced maximum?
• Or should AGENTS.md and the tool configuration be aligned to the same line length?

I do not want to prescribe a specific change before the intended policy is confirmed.

Additional context Duplicate-search note: before opening, search existing issues and PRs for terms like AGENTS.md line length, ruff line-length 120, isort line_length 120, and Python line length 100.