[skills] Sync deployments-cicd with current docs

[vercel-gh-bot-3]

• Stale claim: "# Rollback to the previous production deployment / vercel rollback". In the shipping CLI, running vercel rollback with no argument starts the status subcommand, so nothing is rolled back. The code is const actionOrDeployId = parsedArgs.args[1] || 'status'; in packages/cli/src/commands/rollback/index.ts (vercel/vercel main), and rollbackCommand declares url|deploymentId as required: true. Correction: the example now shows vercel rollback status with the comment "Show pending rollback status (no argument does not roll back)". The vercel rollback <deployment-url-or-id> example below it stays. Docs: https://vercel.com/docs/cli/rollback (last_updated 2026-03-17) documents the subcommand: "Check status for the linked project" / vercel rollback status. agents/deployment-expert.md is regenerated from this section.

Verification

run_plugin_checks passed every step: build (regenerated agents/deployment-expert.md), typecheck, validate, and test (1079 pass, 0 fail).

Test updates

None.

Not changed

• The other claims in SKILL.md and references/ match the current docs and CLI source: --force skips the build cache, vercel build uses Preview env vars by default, --skip-domain + vercel promote, rollback turning off auto-assignment, the Deployment Checks sources, vercel logs --follow/--level/--since, and the CLI reading VERCEL_TOKEN from the environment.
• skills/vercel-cli/references/deployment.md already uses vercel rollback <url>, so it is correct.

Opened automatically by the vercel-plugin drift agent. Review before merge.