Deletes talent/skills.{md,py} and tests/test_skills_hook.py. The new apps/skills/talent pair (skill_observer + skill_editor) plus apps/skills/call.py now owns the full skills pipeline end to end. tests/test_journal_skill.py is unrelated (tests the journal SKILL.md symlinks) and is preserved. Part of Lode B of the skills-observer-editor refactor.