fix(security): restrict skill download target paths

src/agents/skills/tools-dir.ts

@@ -0,0 +1,11 @@
+import path from "node:path";
+import type { SkillEntry } from "./types.js";
+import { safePathSegmentHashed } from "../../infra/install-safe-path.js";
+import { resolveConfigDir } from "../../utils.js";
+import { resolveSkillKey } from "./frontmatter.js";
+
+export function resolveSkillToolsRootDir(entry: SkillEntry): string {
+  const key = resolveSkillKey(entry.skill, entry);
+  const safeKey = safePathSegmentHashed(key);
+  return path.join(resolveConfigDir(), "tools", safeKey);
+}