ci(style): pin ruff-action to 0.15.12

[eexwhyzee]

Summary

Pins astral-sh/ruff-action@v3 to ruff 0.15.12 in both the lint and format steps of style.yml.

Why

ruff-action installs the latest ruff release by default. ruff 0.16.0 (released after 2026‑07‑21) enabled stricter default rules that flag ~98 pre-existing issues across the repo (examples/, renderers/__init__.py, renderers/base.py, …). This turned green PRs red without any code change — e.g. the Laguna‑S‑2.1 routing PR (#111), whose 3-line diff introduced none of the reported errors.

• Against 0.16.0: 98 errors, identical on main and on feature branches.
• Against 0.15.12 (what uv resolves locally): All checks passed!, format clean.

Pinning stops the silent drift so CI reflects the version the repo is actually maintained against. Adopting a newer ruff (and applying its fixes) can then be a deliberate, self-contained change — bump this pin alongside those fixes.

Testing

• uvx ruff@0.15.12 check → All checks passed
• uvx ruff@0.15.12 format --check → 61 files already formatted
• YAML validated

🤖 Generated with Claude Code

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Note

Low Risk
CI-only workflow change; no application code, auth, or runtime behavior affected.

Overview
Pins Ruff to 0.15.12 in the Style workflow so lint and format jobs no longer pull the latest release by default.

Both the Lint and Format astral-sh/ruff-action@v3 steps now set version: "0.15.12", with comments explaining that unpinned CI was drifting (e.g. 0.16.0 stricter rules) and failing PRs without code changes. Future Ruff upgrades are meant to be intentional: bump this pin together with any lint fixes.

^{Reviewed by Cursor Bugbot for commit 7c0cea5. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Pin ruff-action to version 0.15.12 in CI style workflow

Pins both the Ruff Lint and Ruff Format steps in style.yml to version 0.15.12 instead of the action's default latest release, preventing unexpected failures from automatic Ruff upgrades.

^{Macroscope summarized 7c0cea5.}

[macroscopeapp]

Approvability

Verdict: Approved

Pins ruff-action to a specific version to prevent CI drift from upstream releases. This is a minor CI configuration change with no runtime or production impact.

^{You can customize Macroscope's approvability policy. Learn more.}