chore(config): superpowers citers by bare name, routing map, docs, settings

Every superpowers-prefixed skill call in ship-feature, init-project, tour,
deploy, audit-delta, plugin-advisor and lib/analyze-before-plan now names
the vendored skill directly. finishing-a-development-branch is described
as the upstream skill this config does not vendor (gitflow finish is the
integration path). CLAUDE.global.md Skill routing maps the four
non-vendored skills the vendored text still references. settings.json
loses the plugin key and its marketplace block; README, USAGE,
plugin-advisor and the profile skill describe superpowers as vendored
skills, always on, zero plugin cost. CHANGELOG entry with a known
residual.

CLAUDE.global.md

@@ -258,6 +258,12 @@ cryptic names.
 - Design / UI (build, system, audit, polish) → "Design work" below
 - Architecture review → plan-eng-review
 - Before /clear or /compact → capitalize; end-of-session ritual → close
+- superpowers skills are vendored, called by bare name; an upstream
+  `superpowers` prefix names the same skill. Not vendored here:
+  executing-plans → subagent-driven-development
+  finishing-a-development-branch → `gitflow finish` (human signal)
+  systematic-debugging → bugfix
+  verification-before-completion → the verifier gates
 - SEO+GEO → seo (GEO only → geo); W3C + WCAG a11y → web-validate;
   security audit (secrets, CVE, OWASP) → cso
 gstack OFF → its skills (investigate, qa, review, health, retro,