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.

LAUNCH_CHECKLIST.md

@@ -8,15 +8,15 @@ This document summarizes the complete Launch & Marketing Layer implementation fo
 
 ## ✅ Implementation Status
 
-### 1. Supabase Foundation ✓
+### 1. Database & Auth Foundation ✓
 
 | Component | Status | Location |
 |-----------|--------|----------|
-| Auth Flow | ✓ Complete | Existing dev_session + Supabase Auth |
-| Database Structure | ✓ Complete | Supabase migrations in place |
-| Role-Based Access | ✓ Complete | admin-permissions.ts system |
-| Protected Routes | ✓ Complete | middleware.ts |
-| Server Actions Pattern | ✓ Complete | src/actions/*.ts |
+| Auth Flow | ✓ Complete | Neon Auth (Better Auth) + dev_session for local |
+| Database Structure | ✓ Complete | `db/migrations/` applied via `pg` |
+| Role-Based Access | ✓ Complete | `admin-permissions.ts` system |
+| Protected Routes | ✓ Complete | `middleware.ts` |
+| Server Actions Pattern | ✓ Complete | `src/actions/*.ts` |
 
 ### 2. Launch-Ready Features ✓
 
@@ -237,7 +237,7 @@ Track these metrics post-launch:
 
 - **Documentation**: See CLAUDE.md for technical details
 - **Stripe Dashboard**: https://dashboard.stripe.com
-- **Supabase Dashboard**: https://app.supabase.com/project/wnzkhezyhnfzhkhiflrp
+- **Neon Console**: https://console.neon.tech
 - **Vercel Deployments**: https://vercel.com/dashboard
 
 ---