Implement two-layer CAPTCHA bypass

supabase/migrations/20251011003904_dbbdcddf-b9b8-4a45-8cf9-434f8b333e1a.sql

@@ -0,0 +1,9 @@
+-- Add CAPTCHA bypass setting to admin_settings
+INSERT INTO public.admin_settings (setting_key, setting_value, category, description)
+VALUES (
+  'auth.captcha_bypass_enabled',
+  'false',
+  'auth',
+  'Allow CAPTCHA bypass for authentication (development only - requires VITE_ALLOW_CAPTCHA_BYPASS=true in environment)'
+)
+ON CONFLICT (setting_key) DO NOTHING;