nodespace uninstall only removes the Claude Code skill directory, leaving Codex/Gemini CLI/OpenCode/Pi skill files behind #2964

Problem

A Codex/Gemini CLI/OpenCode/Pi user who fully uninstalls NodeSpace via nodespace uninstall sees a clean, unqualified "NodeSpace uninstalled" message while their harness's skill files silently remain on disk — recoverable only by knowing to separately run nodespace skill uninstall first.

Root cause

remove_claude_skill (packages/cli/src/commands/uninstall.rs:84) hardcodes ~/.claude/skills/nodespace as the only path removed, via fs::remove_dir_all. commands/skill.rs (same crate) already documents and implements skill installation and removal for all four supported harnesses — its own uninstall() shells out to the real cross-harness installer and reports per-agent removal — but uninstall::run never calls that path; it only ever touches the one Claude-Code-specific directory directly. There is no shared helper, no test enforcing parity between the two commands, and no warning printed when non-Claude skill directories are detected but left behind.

Suggested fix

Have uninstall::run call into skill::run_installer_subcommand(&installer, "uninstall") (or the equivalent multi-harness removal logic) instead of remove_claude_skill's hardcoded single-path fs::remove_dir_all.

Found via the 2026-09-25 full-repo code sweep (finding #14 of 84 in CODE_SWEEP_FINDINGS_2026-09-25.md). Severity: medium. Category: architecture.