backend-services

Instruction file imported from dannyzia/carenet2 (.github/instructions/backend-services.instructions.md). Copyright stays with the author.

You are working on the backend service layer for CareNet 2.

• Use sbRead, sbWrite, sb, and currentUserId from src/backend/services/_sb.ts for all Supabase operations. Do not duplicate query boilerplate.
• Preserve all USE_SUPABASE mock fallback branches. Never remove them.
• Use supabase.channel(...).on('postgres_changes', ...) for realtime subscriptions.
• Always clean up channels and listeners on component unmount or hook teardown.
• Write flows that must survive disconnects should route through the Dexie queue in src/backend/offline/.
• Check supabase/functions/ and supabase/migrations/ before changing behavior that depends on them.
• Keep conflict-prone flows retry-safe and idempotent.
• Do not introduce Firebase, Prisma, TanStack Query, or any alternative data layer.