chore(supabase): full purge — remove all Supabase references from codebase

- Delete supabase/ directory (config.toml, push-migrations.js,
  ADMIN_CREATE_STOP_FIX.sql, 137 archived migration files)
- Remove @supabase/ssr and @supabase/supabase-js from package.json
- Strip *.supabase.co from next.config.ts image hostnames
- Strip https://*.supabase.co from vercel.json CSP connect-src
- Remove 'supabase/**' ignore from eslint.config.mjs
- Clean supabase references from src/lib/db.ts, vitest.config.ts,
  db/seeds/2026-tuxedo-tour-stops.sql, src/actions/storefront.ts,
  scripts/import-tuxedo-stops.ts comments
- Rewrite env-var docs in README, ENVIRONMENT, PRODUCTION_SETUP,
  PRODUCTION_DEPLOYMENT_CHECKLIST, LAUNCH_CHECKLIST, CLAUDE,
  MEMORY, REPORT to drop NEXT_PUBLIC_SUPABASE_URL /
  SUPABASE_SERVICE_ROLE_KEY / supabase link / supabase CLI references

The canonical migration runner is now scripts/migrate.js (uses pg
directly via DATABASE_URL). Migrations live in db/migrations/. The
Supabase CLI is no longer in the codebase. The only remaining
'@supabase/*' in the dep tree is @supabase/auth-js as a transitive
of @neondatabase/auth (Neon Auth / Better Auth).

Final source scan: grep -rln '@supabase\|rest/v1\|supabase\.co'
src/ tests/ db/ scripts/ next.config.ts vercel.json eslint.config.mjs
package.json returns zero. Verification: npm install clean
(11 added, 21 removed, 12 changed), tsc shows same 17 pre-existing
errors (Stripe dahlia API version + fetch preconnect mocks),
vitest 172/175 (3 pre-existing failures in getAdminUser.test.ts),
lint shows same 14 pre-existing errors. Live-tested: dev server
boots in 248ms, public storefronts (/) (/login) (/pricing) (/tuxedo)
(/indian-river-direct) all return 200; /admin/v2?demo=1 reaches 200
after dev_session redirect; storefront renders real brand content.

supabase/migrations/.archived/201_seed_data.sql

@@ -1,23 +0,0 @@
--- Seed data for production development and testing
-
-BEGIN;
-
--- =============================================================================
--- DEMO BRANDS
--- =============================================================================
-
-INSERT INTO brands (id, name, slug, plan_tier, max_users, max_stops_monthly, max_products, stripe_customer_id, created_at)
-VALUES 
-  ('a1b2c3d4-e5f6-7890-abcd-ef1234567890', 'Sunrise Farms', 'sunrise-farms', 'enterprise', 10, 100, 500, 'cus_demo_sunrise', NOW()),
-  ('b2c3d4e5-f6a7-8901-bcde-f12345678901', 'Green Valley Organics', 'green-valley', 'farm', 5, 50, 250, 'cus_demo_green', NOW()),
-  ('c3d4e5f6-a7b8-9012-cdef-123456789012', 'Orchard Fresh', 'orchard-fresh', 'starter', 2, 10, 50, 'cus_demo_orchard', NOW())
-ON CONFLICT (id) DO NOTHING;
-
-
--- NOTE: The remainder of the original seed data (products, stops, orders, water logs, etc.)
--- has been removed from this migration because the column layouts in the live DB
--- (shaped by many prior migrations) no longer match the INSERTs here.
--- The 3 demo brands above will be inserted (now that plan_tier/max_* columns exist).
--- Use the admin UI or separate scripts to populate test data as needed.
-
-COMMIT;