Fixes public packaging and installability for grill-all.\n\nIncludes:\n- Codex marketplace layout fix: marketplace now points to plugins/grill-all.\n- Adds plugins/grill-all/.codex-plugin/plugin.json for Codex plugin discovery.\n- README install commands updated for Codex and Claude Code.\n- Claude Code install uses explicit HTTPS URL.\n- Codex user skill path corrected to CODEX_HOME/default ~/.codex/skills.\n- Claude marketplace description metadata added.\n- Durable decision documentation rules now require write authorization or confirmation.\n- Adds SECURITY.md, CHANGELOG.md, and scripts/verify-packaging.sh.