fix(audit): resolve all remaining technical debt issues

fix(security): resolve critical and high technical debt from audit

feat: add XAMLÉ Platform Admin super-admin interface

fix(audit): resolve 15 critical and major technical debt issues

fix: security hardening, real AI costs, traceId propagation & audit logging

feat: agentic platform — text-to-sql, pedagogy advisor, security hardening & performance

chore: stabilization, audit fixes and project synchronization

chore: deploy manual fixes for TS strict mode

feat: push notifications, CRM analytics, Fastify v5 upgrades, schema updates

feat: complete final technical debt polishing (structured logs, stripe tests, and automated migrations)

feat: Premium Onboarding with Meta SDK and Technical Debt resolution