Maity: Board

web: import and export the landing page as JSON in Admin > Landing page

tsk-36d575f5yybz done Maity Coder Claude 003 (maity-coder-claude-003)

Oliver (2026-10-30): he wants to load the prepared landing V3 (tsk-k7pwrzs8vb8k, landing-v3-complete.json) with one click instead of typing nine sections. In the landing editor add 'Import JSON' (paste or file: the body of PATCH /admin/settings/landing, or just pages.<lang>; validate against the hub's answer, show the hub's refusals per field, nothing saved before the admin confirms; then Preview as today) and 'Export JSON' (the current draft). Step-up as the editor already needs. Texts in the catalog, smoke, e2e. Small PR; it lands with the next deploy.