feat(sdk): compile-time schema access for strong types (codegen) #259

Area: sdk — backlog feature (SDK epic) · promoted from #194

What: optional compile-time/codegen access to table schemas so SDK consumers get strong types end-to-end.

Context: the SDK already has a codegen script; formalizing schema → TS types gives type safety for known tables. Security TBD — build-time schema access shouldn't expose more than intended.

Scope: a codegen/types pipeline from schema → TS; decide the security boundary (which schemas a dev may pull at build time).

Related: SDK epic #194; runtime policy-scoped schema (filed alongside); helpful TS errors #198.

Promoted from the #194 SDK-epic backlog ("Later / not yet scoped"); 2026-06-04.