fix(runtime): 턴 데몬 전용 heap 상한을 추가

공용 빌드·API heap과 턴 데몬 heap을 분리하고 Compose 안전 검증과 운영 문서를 함께 갱신한다.

test/validate-compose-model.test.mjs

@@ -7,6 +7,7 @@ const safeRuntime = {
   environment: {
     CORE_SOURCE_MODE: 'clone',
     NODE_OPTIONS: '--max-old-space-size=1536',
+    TURN_DAEMON_NODE_OPTIONS: '--max-old-space-size=3072',
     RAYON_NUM_THREADS: '2',
     GATEWAY_IMAGE_UPLOAD_URL: 'https://sam-image.hided.net',
     GATEWAY_IMAGE_UPLOAD_SECRET_FILE: '/run/secrets/image_upload_core2026_secret',
@@ -87,10 +88,12 @@ test('rejects missing or excessive build memory and parallelism limits', () => {
     environment: {
       CORE_SOURCE_MODE: 'clone',
       NODE_OPTIONS: '--max-old-space-size=4096',
+      TURN_DAEMON_NODE_OPTIONS: '--max-old-space-size=8192',
       RAYON_NUM_THREADS: '8',
     },
   };
   const errors = validateComposeModel({ services: { runtime } }, 'production');
   assert.ok(errors.some((error) => error.includes('Node heap limit')));
+  assert.ok(errors.some((error) => error.includes('turn daemon Node heap limit')));
   assert.ok(errors.some((error) => error.includes('Rayon thread count')));
 });