Move Canvas, Discord, Slack, voice-call, and WhatsApp skill docs from the root bundled skill tree into their owning plugin packages, with manifest skills declarations and docs/test path updates.
Validation:
- node --import tsx scripts/sync-plugin-versions.ts --check
- node scripts/run-vitest.mjs src/skills/loading/env-path-guidance.test.ts
- autoreview clean
- Crabbox Azure pnpm check:changed run_59ba76511d57 / lease cbx_cbc6750dad72
- wrapper prepare passed pnpm install --frozen-lockfile, pnpm build, and pnpm check before the oversized full local pnpm test was stopped
Follow-up: #95132 remains as the stacked PR for the rest of the starter-skill/Sherpa/ClawHub work.
