Emit the 6 gsd-ns-* routers as the only top-level skill bundles and nest
the ~61 concrete skills under <router>/skills/<name>/SKILL.md on runtimes
with confirmed non-recursive skill loaders (claude global, cline, qwen,
hermes, augment, trae, antigravity). Router bodies rewrite their routing
tables from Skill-tool dispatch to a Read skills/<name>/SKILL.md pattern.
Recursive/unconfirmed loaders (cursor, codex, copilot, windsurf, codebuddy,
opencode, kilo) keep the flat layout. Completes the v1.40 namespace
architecture (#2792) so the eager skill listing drops to ~6 entries.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>