fix(curator): protect hub skills by frontmatter name

[LeonSGP43]

Summary

• Extend the curator provenance guard for hub-installed skills to include the installed skill's SKILL.md frontmatter name, not only the hub slug.
• Resolve hub lock install_path entries under the skills directory before reading frontmatter, so slug/display-name mismatches stay protected.
• Add a regression for a hub slug getnote whose installed skill is named Get笔记.

Why

Issue #19293 reports that the curator treats hub-installed skills with localized or otherwise non-slug name fields as agent-created. The lock file tracks the hub slug, while curator candidate discovery compares the SKILL.md name, so getnote did not protect Get笔记.

Verification

• scripts/run_tests.sh tests/tools/test_skill_usage.py - 39 passed, 4 existing event-loop deprecation warnings

Fixes #19293

[teknium1]

Salvaged via PR #20194 (#20194). Your commit was cherry-picked onto current main with authorship preserved in git log; I added one test tweak (mark_agent_created("my-skill")) because the positive assertion relied on provenance-marker behavior added in #19618/#19621 after your branch. Thanks for the fix!