fix(skills): preserve official optional-skill frontmatter names

[Qwinty]

Summary

This fixes the official optional-skill branch of the skill-name mismatch bug class:

• preserve the SKILL frontmatter name when fetching official optional skills for install
• treat hub-installed skills as aliases of their installed SKILL frontmatter name in hermes skills list
• add regressions for install-time naming and list classification

Problem

OptionalSkillSource.fetch() used the directory slug as bundle.name, while official search/list/inspect surface the SKILL frontmatter name.

That creates a mismatch for optional skills whose directory and frontmatter diverge. Example:

• directory: optional-skills/productivity/here-now/
• frontmatter: name: here.now

Before this patch:

1. install records the hub entry under here-now
2. _find_all_skills() returns here.now
3. hermes skills list fails to match the hub lock entry and falls through to local

So an official skill can appear as local after install.

This is not dot-specific: I scanned optional-skills/ and found 14 official skills whose directory name differs from frontmatter name, including here.now and devops/cli -> inference-sh-cli.

Why both changes

• Fetch/install alignment fixes new installs going forward.
• Frontmatter aliasing in do_list() keeps already-installed skills classified correctly even if they were installed before this patch under the old directory-slug name.

Verification

pytest tests/hermes_cli/test_skills_hub.py -q

Passed locally:

• 24 passed

Related

• skill_view resolves by directory name but skills_list displays frontmatter name — mismatch causes 'not found' #17914
• [Bug]: skill_view/skills_list name mismatch breaks agent tool-calling loop — model can't load skills it discovers #18872
• fix(skills): add frontmatter-name fallback in skill_view to resolve name mismatch #18901

[Qwinty]

Closing this PR because the branch accidentally included unrelated changes. I will reopen a clean, minimal PR with only the skills hub fix.