Update agents/rules/writing-skills.md to recommend affirmative framing (preferring ALWAYS over NEVER) for rules and guardrails, avoiding negative constraint neglect. Also update frontmatter to model_decision so Jetski can discover this rule. TAG=agy R=leszeks@chromium.org Change-Id: I34d1433cb8c75657e120190b582926384c322b04 Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/8521003 Reviewed-by: Leszek Swirski <leszeks@chromium.org> Commit-Queue: Clemens Backes <clemensb@chromium.org> Reviewed-by: Marco Vitale <mrcvtl@chromium.org> Cr-Commit-Position: refs/heads/main@{#110542}