B2BEA.org Rebuild build-execution S-04

• Portal runtime now fetches a page-declared authenticated summary endpoint after /api/access/decision allows access.
• Vendor shell declares /api/access/vendor-summary and renders returned vendor name plus category/city/region metadata into non-sensitive placeholders.
• Company shell declares /api/access/company-summary and renders returned organization name plus kind/status/domain metadata into non-sensitive placeholders.
• Summary fetch failures are non-blocking so access-approved shells still reveal.
• No CSS changes were made; the slice stayed inside the design-system governance constraint.

Start Slice 5 from origin/main and add the next data-backed authenticated portal workflow, preferably a vendor/company profile read/update path with TDD and no rogue CSS.