fix: revert ADMIN_ENDPOINT to HTTP, remove X-Forwarded-Proto

Internal Docker traffic is HTTP. Traefik handles TLS termination
for external access. TRUST_PROXY_HEADER lets Logto detect HTTPS
from Traefik's forwarded headers automatically.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker-compose.yml

@@ -67,7 +67,7 @@ services:
     environment:
       DB_URL: postgres://${POSTGRES_USER:-cameleer}:${POSTGRES_PASSWORD:-cameleer_dev}@postgres:5432/logto
       ENDPOINT: ${PUBLIC_PROTOCOL:-https}://${PUBLIC_HOST:-localhost}
-      ADMIN_ENDPOINT: ${PUBLIC_PROTOCOL:-https}://${PUBLIC_HOST:-localhost}:3002
+      ADMIN_ENDPOINT: http://${PUBLIC_HOST:-localhost}:3002
       TRUST_PROXY_HEADER: 1
     healthcheck:
       test: ["CMD-SHELL", "node -e \"require('http').get('http://localhost:3001/oidc/.well-known/openid-configuration', r => process.exit(r.statusCode === 200 ? 0 : 1)).on('error', () => process.exit(1))\""]