meta(risk): Sync conservative legacy labels

Add a maintainers script to safely promote high-confidence legacy risk labels from unknown to concrete values, cover it with tests, and regenerate the canonical skill artifacts and plugin copies. This reduces the legacy unknown backlog without forcing noisy classifications that still need manual review.

plugins/antigravity-bundle-full-stack-developer/skills/database-design/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: database-design
 description: "Database design principles and decision-making. Schema design, indexing strategy, ORM selection, serverless databases."
-risk: unknown
+risk: safe
 source: community
 date_added: "2026-02-27"
 ---

plugins/antigravity-bundle-full-stack-developer/skills/senior-fullstack/SKILL.md

@@ -1,7 +1,7 @@
 ---
 name: senior-fullstack
 description: "Complete toolkit for senior fullstack with modern tools and best practices."
-risk: unknown
+risk: critical
 source: community
 date_added: "2026-02-27"
 ---