Summary

• Adds a new unlisted page documenting the Commercial Plan at account/plans/commercial.mdx.
• The page is hidden from the sidebar/sitemap (unlisted: true) and carries noindex, nofollow, noarchive, nosnippet so it is not indexed by search engines or surfaced in DocSearch.
• The plan is sold through the sales team only — all CTAs link to the absolute https://www.marketdata.app/contact/ URL, matching the existing pattern in api/cors.mdx.

Test plan

• Verified on staging: page reachable at https://www-staging.marketdata.app/docs/account/plans/commercial
• Confirmed contact links resolve to https://www.marketdata.app/contact/ (not the docs-prefixed /docs/contact/)
• Confirmed page is excluded from the staging sidebar
• Post-deploy integration + e2e tests passed on staging