fix(clients): resolve file import dialog error and SSE 401

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

feat(crm-ux): tag management, unread badge, handoff release UI

feat(admin): UX non-tech complète + i18n 4 langues

feat(billing): complete billing system, push notifications, and tech debt fixes

fix(admin): sidebar active states, responsive mobile drawer, correct nav labels

feat: implement whatsapp templates management with security hardening, audit logs, and crm integration

chore: stabilization, audit fixes and project synchronization

feat: implement bulk whatsapp campaigns with BullMQ and modular activation refactor (isCrmActive/isEdTechActive)

feat: implement RoleGuard for centralized authorization

style: standardize frontend imports using @/ alias

refactor: extract shell and sidebar to MainLayout