Major release: pricing model split into three customer archetypes (Solo / SMB, Agency, White-Label). Each plan now has billing_archetype, annual_discount_pct, max_client_orgs, allow_overage, custom_pricing flag.
New endpoints: POST /billing/change-plan (real-time mid-cycle upgrades with Stripe proration), GET /billing/my-entitlements (effective features per org), GET /billing/plans-with-features (full plan + feature matrix).
White-label hub at /white-label: custom domain, logo, brand colors, hide-OmniMark toggle, Stripe Connect Express onboarding for split-payment resellers.
Multi-account: SocialAccount.external_account_id + UniqueConstraint(org_id, platform, external_account_id); new AdAccount table; OAuth append flow updated across all 7 social providers; per-plan caps enforced.