Supabase migration

I have a working web app (single HTML/JS file, ~2,400 lines, vanilla JS) for commercial/cost tracking on a project. It currently stores everything in browser localStorage — fully functional, but single-device, no backup, no sharing. I want to migrate it to Supabase (Postgres + Auth + Realtime). Scope: schema design across ~6 data domains (register, costs, line items, logs, config/history, checklist); auth with 2 roles (edit / read-only); proper RLS policies; one-time data migration; rewrite the frontend’s save/load layer to use Supabase; real-time sync so the read-only user sees live data; deploy to free static hosting. This is step one toward a small internal platform — the same backend may be reused for other tools later. Trial task first (paid separately, ~€100-150): set up Supabase + auth (2 roles) + migrate one table with tested RLS for both roles. We’ll decide on the full scope based on this. Full scope budget: fixed price, propose your own breakdown. Requirements: hands-on Supabase RLS experience for multi-role apps (send a sanitized example), comfortable reading existing JS code, clear written English. To apply: briefly describe your approach to the data-layer rewrite, share an RLS example, and your availability/rate.