fix(curator): scan nested archive subdirs in restore_skill

restore_skill() in tools/skill_usage.py used archive_root.iterdir(), which
only walked the top level of .archive/. Skills archived under nested layouts
(e.g. .archive/openclaw-imports/<skill>/ from older archive paths or
external imports) were invisible to both the exact-match and prefix-match
candidate scans, surfacing as a misleading "skill '<name>' not found in
archive" error even though the directory existed on disk.

Switch both candidate scans to archive_root.rglob('*') so the lookup
descends into category subdirectories.

Fixes #17942

tests/tools/test_skill_usage.py

@@ -315,6 +315,41 @@ def test_restore_skill_moves_back(skills_home):
     assert get_record("temp-skill")["state"] == "active"
 
 
+def test_restore_skill_finds_nested_archive_subdir(skills_home):
+    """Skills archived under nested category subdirs (e.g.
+    .archive/<category>/<skill>/) — left behind by older archive layouts or
+    external imports — must still be restorable by name."""
+    from tools.skill_usage import restore_skill, get_record
+    skills_dir = skills_home / "skills"
+    nested = skills_dir / ".archive" / "openclaw-imports" / "nested-skill"
+    nested.mkdir(parents=True)
+    (nested / "SKILL.md").write_text(
+        "---\nname: nested-skill\ndescription: x\n---\n", encoding="utf-8",
+    )
+
+    ok, msg = restore_skill("nested-skill")
+    assert ok, msg
+    assert (skills_dir / "nested-skill" / "SKILL.md").exists()
+    assert not nested.exists()
+    assert get_record("nested-skill")["state"] == "active"
+
+
+def test_restore_skill_finds_nested_timestamped_prefix(skills_home):
+    """Prefix-match path (timestamped dupes) must also descend into nested
+    archive subdirs, not just .archive/ top-level."""
+    from tools.skill_usage import restore_skill
+    skills_dir = skills_home / "skills"
+    nested = skills_dir / ".archive" / "imports" / "dup-skill-20260101000000"
+    nested.mkdir(parents=True)
+    (nested / "SKILL.md").write_text(
+        "---\nname: dup-skill\ndescription: x\n---\n", encoding="utf-8",
+    )
+
+    ok, msg = restore_skill("dup-skill")
+    assert ok, msg
+    assert (skills_dir / "dup-skill" / "SKILL.md").exists()
+
+
 def test_archive_collision_gets_suffix(skills_home):
     from tools.skill_usage import archive_skill
     skills_dir = skills_home / "skills"

tools/skill_usage.py

@@ -385,11 +385,13 @@ def restore_skill(skill_name: str) -> Tuple[bool, str]:
     if not archive_root.exists():
         return False, "no archive directory"
 
-    # Try exact name match first, then any prefix match (for timestamped dupes)
-    candidates = [p for p in archive_root.iterdir() if p.is_dir() and p.name == skill_name]
+    # Try exact name match first, then any prefix match (for timestamped dupes).
+    # Recursive walk handles nested archive layouts (e.g. .archive/<category>/<skill>/)
+    # left behind by older archive paths or external imports.
+    candidates = [p for p in archive_root.rglob("*") if p.is_dir() and p.name == skill_name]
     if not candidates:
         candidates = sorted(
-            [p for p in archive_root.iterdir()
+            [p for p in archive_root.rglob("*")
              if p.is_dir() and p.name.startswith(f"{skill_name}-")],
             reverse=True,
         )