Adds an integration-e2e job to ci.yml alongside the fast hermetic check job. It
brings up the Supabase CLI stack, applies the canonical scripts/schema.sql +
seed.sql, then runs the integration suite (psql-driven shipped-SQL: RPCs / RLS /
triggers / constraints) and the Playwright e2e suite (chromium) against the app
wired to that stack (env sourced from `supabase status`).
The integration suite self-skips when no DB is reachable, so a missing DB could
pass silently. Two guards prevent that: an explicit `select 1` reachability
check, and a post-run assertion that fails the job when the suite executed 0
tests (parsed from the vitest json reporter).
Auto-seed is disabled for the ephemeral CI checkout (seed.sql needs tables that
schema.sql creates outside the migration path); schema + seed are applied
explicitly. Local dev is unaffected.
Validated locally: integration suite (58 tests) and both e2e specs (53 tests,
chromium) pass against the real local stack.