fix(skills): prune dependency/venv dirs from all skill scanners (#30042)

* fix(skills): skip dependency dirs in skill scan

* fix(skills): widen sibling rglob scanners to use shared exclusion set

Follow-up to PR #29968. The contributor's PR widened EXCLUDED_SKILL_DIRS
in the canonical walker (iter_skill_index_files), which fixes the
user-visible discovery path. This commit sweeps the ~12 other
rglob('SKILL.md') sites that did their own ad-hoc filtering — most only
checked .git/.hub, some had no filter at all — so dependency dirs
(.venv, node_modules, site-packages, etc.) cannot leak ghost skills
through the secondary paths.

Adds agent.skill_utils.is_excluded_skill_path(path) helper. Migrates
all 13 sites to use it. Removes 3 hardcoded duplicate filter sets.

Sites touched:
  agent/curator_backup.py        - skill backup file count
  gateway/run.py                 - disabled-skill response (2 sites)
  hermes_cli/dump.py             - skill count in env dump
  hermes_cli/profile_describer.py- profile description (2 sites)
  hermes_cli/profile_distribution.py - profile install count
  hermes_cli/profiles.py         - profile skill count
  hermes_cli/skills_hub.py       - category detection
  tools/skill_manager_tool.py    - skill name lookup (already used set, now uses helper)
  tools/skill_usage.py           - usage tracking + skill dir lookup (2 sites)
  tools/skills_hub.py            - optional skills find + scan (2 sites)
  tools/skills_sync.py           - bundled skills sync

E2E verified with the exact reported shape
(bring/scripts/.venv/.../typer/.agents/skills/typer/SKILL.md): no
sibling site picks up the ghost skill, all five legit-skill counts
still return 1.

* chore(infographic): retro-pop-grid bento for PR #30042 skill-scanner sweep

---------

Co-authored-by: helix4u <4317663+helix4u@users.noreply.github.com>

gateway/run.py

@@ -1109,7 +1109,7 @@ def _check_unavailable_skill(command_name: str) -> str | None:
     normalized = command_name.lower().replace("_", "-")
     try:
         from tools.skills_tool import _get_disabled_skill_names
-        from agent.skill_utils import get_all_skills_dirs
+        from agent.skill_utils import get_all_skills_dirs, is_excluded_skill_path
         disabled = _get_disabled_skill_names()
 
         # Check disabled skills across all dirs (local + external)
@@ -1117,7 +1117,7 @@ def _check_unavailable_skill(command_name: str) -> str | None:
             if not skills_dir.exists():
                 continue
             for skill_md in skills_dir.rglob("SKILL.md"):
-                if any(part in {'.git', '.github', '.hub', '.archive'} for part in skill_md.parts):
+                if is_excluded_skill_path(skill_md):
                     continue
                 slug, declared_name = _skill_slug_from_frontmatter(skill_md)
                 if not slug or not declared_name:
@@ -1136,6 +1136,8 @@ def _check_unavailable_skill(command_name: str) -> str | None:
         optional_dir = get_optional_skills_dir(repo_root / "optional-skills")
         if optional_dir.exists():
             for skill_md in optional_dir.rglob("SKILL.md"):
+                if is_excluded_skill_path(skill_md):
+                    continue
                 slug, _declared = _skill_slug_from_frontmatter(skill_md)
                 if not slug:
                     continue