docs: mention pre-commit in AGENTS.md and CLAUDE.md

[Copilot]

The pre-commit infrastructure (.pre-commit-config.yaml, dev dependency, CONTRIBUTING.md setup step) was already in place, but agent-facing guides (AGENTS.md, CLAUDE.md) had no mention of it — meaning agents and developers would skip pre-commit install and only catch format/lint failures in CI.

Changes

• AGENTS.md — Added a note after the Commands section instructing agents to run pre-commit install once after cloning, with a brief description of what the hooks do
• CLAUDE.md — Added pre-commit install as the first "Do" item so it's the highest-priority setup step Claude sees

Original prompt

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This section details on the original issue you should resolve

<issue_title>[infra] Add .pre-commit-config.yaml with ruff format + check hooks</issue_title>
<issue_description>## Problem

The repo has no .pre-commit-config.yaml. Developers and AI agents can commit unformatted or unlinted code, only catching issues after pushing to CI. This wastes CI cycles and slows feedback loops, especially for agent-driven development where agents submit frequent PRs.

Evidence:

• .pre-commit-config.yaml — missing
• pyproject.toml [project.optional-dependencies] dev does not include pre-commit
• CI already runs ruff format --check and ruff check (.github/workflows/ci.yml)
• CONTRIBUTING.md mentions make fmt / make lint but not pre-commit hooks

Proposal

Add a .pre-commit-config.yaml with ruff-only hooks (format + check). mypy is excluded from pre-commit to keep hooks fast (mypy runs in CI).

Hook configuration

repos:
  - repo: https://github.com/astral-sh/ruff-pre-commit
    rev: v0.4.x  # pin to version matching pyproject.toml
    hooks:
      - id: ruff-format
      - id: ruff
        args: [--fix]

Supporting changes

• Add pre-commit to dev dependencies in pyproject.toml
• Update CONTRIBUTING.md with pre-commit install setup step
• Mention pre-commit in AGENTS.md and CLAUDE.md

Acceptance criteria

• .pre-commit-config.yaml created with ruff-format + ruff hooks
• ruff version pinned to match pyproject.toml (>=0.4)
• pre-commit added to [project.optional-dependencies] dev in pyproject.toml
• CONTRIBUTING.md updated with pre-commit install step in Setup section
• AGENTS.md updated to mention pre-commit
• All existing code passes hooks without modifications (green-only constraint)
• make ci still passes

File paths

• .pre-commit-config.yaml (create)
• pyproject.toml (edit — add pre-commit to dev deps)
• CONTRIBUTING.md (edit — add pre-commit install step)
• AGENTS.md (edit — mention pre-commit)

Dependencies

• None (independent quick win)

Estimated effort

S (1 day)</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes [infra] Add .pre-commit-config.yaml with ruff format + check hooks #93

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[Copilot]

Pull request overview

Updates agent-facing documentation so contributors (including AI agents) install and benefit from the repo’s existing pre-commit hooks, reducing CI-only feedback for formatting/lint issues.

Changes:

• Add pre-commit install as a top-priority “Do” item in CLAUDE.md.
• Add a short post-clone note in AGENTS.md explaining the ruff hooks run on commit.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
CLAUDE.md	Adds an explicit “pre-commit install” setup step to the Claude checklist.
AGENTS.md	Documents running pre-commit install after cloning and what hooks run.

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