chore: generate typed Supabase client and burn down the TypeScript error baseline

[MaxBrych]

Problem

The repo carries a known baseline of a few hundred pre-existing tsc errors, almost all cascading from an untyped Supabase client (queries return never/any). This is the single biggest code-health debt in the repo, and it makes pnpm typecheck useless as a signal for contributors (see the note in CONTRIBUTING.md).

Approach

1. Generate types from the live schema: supabase gen types typescript (or via the Supabase MCP / dashboard) → check in as e.g. packages/config/supabase-types.ts or per-app types/supabase.ts
2. Type the client instances: createClient<Database>(...) in apps/expo/lib/ and apps/web/src/lib/
3. Fix the fallout incrementally — this can be split across several PRs (per-app, per-feature-area). Partial progress is welcome.

Acceptance criteria

• Supabase clients are constructed with a generated Database type
• pnpm typecheck error count drops meaningfully (report before/after in the PR)
• A documented command or script to regenerate types when the schema changes