feat(runtime): 정적 프런트엔드와 격리 빌더를 구성한다

Caddy가 불변 아티팩트를 직접 제공하고 runtime과 builder의 자원·비밀 경계를 분리한다.

Gateway active release ref를 재기동에 복원하고 production/development/smoke 모델 검증을 확장한다.

test/validate-compose-model.test.mjs

@@ -20,6 +20,9 @@ const safeRuntime = {
     IMAGE_SYNC_SECRET_FILE: '/run/secrets/image_sync_core2026_secret',
     VITE_IMAGE_PUBLIC_URL: 'https://sam-image.hided.net',
     VITE_GATEWAY_USER_ICON_BASE_URL: 'https://sam-image.hided.net/icons',
+    FRONTEND_SERVE_MODE: 'static',
+    RELEASE_BUILDER_URL: 'http://builder:15100',
+    GATEWAY_ACTIVE_RELEASE_GIT_REF: 'refs/sammo/active-gateway',
   },
   volumes: [
     {
@@ -28,6 +31,12 @@ const safeRuntime = {
       target: '/run/secrets/image_upload_core2026_secret',
       read_only: true,
     },
+    {
+      type: 'volume',
+      source: 'frontend-artifacts',
+      target: '/srv/frontend-artifacts',
+      read_only: false,
+    },
     {
       type: 'bind',
       source: '/secrets/image_sync_core2026_secret',
@@ -42,12 +51,46 @@ const safeRuntime = {
   pids_limit: 256,
 };
 
+const safeBuilder = {
+  environment: {
+    NODE_OPTIONS: '--max-old-space-size=3072',
+    RAYON_NUM_THREADS: '2',
+  },
+  restart: 'unless-stopped',
+  mem_limit: String(4 * 1024 * 1024 * 1024),
+  memswap_limit: String(4 * 1024 * 1024 * 1024),
+  cpus: 4,
+  pids_limit: 256,
+};
+
+const safeCaddy = {
+  restart: 'unless-stopped',
+  volumes: [
+    {
+      type: 'volume',
+      source: 'frontend-artifacts',
+      target: '/srv/frontend-artifacts',
+      read_only: true,
+    },
+  ],
+};
+
+const safeServices = () => ({
+  runtime: structuredClone(safeRuntime),
+  builder: structuredClone(safeBuilder),
+  caddy: structuredClone(safeCaddy),
+});
+
 test('accepts a bounded production runtime', () => {
-  assert.deepEqual(validateComposeModel({ services: { runtime: safeRuntime } }, 'production'), []);
+  assert.deepEqual(validateComposeModel({ services: safeServices() }, 'production'), []);
 });
 
 test('accepts a literal, non-restarting development model', () => {
-  const services = Object.fromEntries(['postgres', 'redis', 'caddy'].map((name) => [name, { restart: 'no' }]));
+  const services = safeServices();
+  services.postgres = { restart: 'no' };
+  services.redis = { restart: 'no' };
+  services.builder.restart = 'no';
+  services.caddy.restart = 'no';
   services.runtime = {
     ...safeRuntime,
     restart: 'no',
@@ -61,13 +104,19 @@ test('accepts a literal, non-restarting development model', () => {
 });
 
 test('accepts a bounded, non-restarting production smoke model', () => {
-  const services = Object.fromEntries(['postgres', 'redis', 'caddy'].map((name) => [name, { restart: 'no' }]));
+  const services = safeServices();
+  services.postgres = { restart: 'no' };
+  services.redis = { restart: 'no' };
+  services.builder.restart = 'no';
+  services.caddy.restart = 'no';
   services.runtime = { ...safeRuntime, restart: 'no' };
   assert.deepEqual(validateComposeModel({ services }, 'smoke'), []);
 });
 
 test('rejects an unbounded or production-mode development runtime', () => {
-  const services = Object.fromEntries(['postgres', 'redis', 'caddy'].map((name) => [name, { restart: 'unless-stopped' }]));
+  const services = safeServices();
+  services.postgres = { restart: 'unless-stopped' };
+  services.redis = { restart: 'unless-stopped' };
   services.runtime = {
     environment: { CORE_SOURCE_MODE: 'bind', RUNTIME_MODE: 'production' },
     restart: 'unless-stopped',
@@ -92,7 +141,9 @@ test('rejects missing or excessive build memory and parallelism limits', () => {
       RAYON_NUM_THREADS: '8',
     },
   };
-  const errors = validateComposeModel({ services: { runtime } }, 'production');
+  const services = safeServices();
+  services.runtime = runtime;
+  const errors = validateComposeModel({ services }, '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')));