feat: runtime manager

lobby/internal/config/config_test.go

@@ -40,6 +40,7 @@ func TestDefaultConfig(t *testing.T) {
 	assert.Equal(t, 5*time.Second, cfg.GM.Timeout)
 	assert.Equal(t, 30*time.Second, cfg.EnrollmentAutomation.Interval)
 	assert.Equal(t, time.Hour, cfg.PendingRegistration.Interval)
+	assert.Equal(t, "galaxy/game:{engine_version}", cfg.RuntimeManager.EngineImageTemplate)
 	assert.Equal(t, "galaxy-lobby", cfg.Telemetry.ServiceName)
 	assert.Equal(t, "none", cfg.Telemetry.TracesExporter)
 	assert.Equal(t, "none", cfg.Telemetry.MetricsExporter)
@@ -114,6 +115,7 @@ func TestLoadFromEnvOverrides(t *testing.T) {
 	t.Setenv("LOBBY_NOTIFICATION_INTENTS_STREAM", "alt:intents")
 	t.Setenv("LOBBY_ENROLLMENT_AUTOMATION_INTERVAL", "45s")
 	t.Setenv("LOBBY_RACE_NAME_EXPIRATION_INTERVAL", "15m")
+	t.Setenv("LOBBY_ENGINE_IMAGE_TEMPLATE", "registry.example.com/galaxy/game:{engine_version}")
 	t.Setenv("OTEL_SERVICE_NAME", "galaxy-lobby-test")
 
 	cfg, err := LoadFromEnv()
@@ -129,6 +131,7 @@ func TestLoadFromEnvOverrides(t *testing.T) {
 	assert.Equal(t, "alt:intents", cfg.Redis.NotificationIntentsStream)
 	assert.Equal(t, 45*time.Second, cfg.EnrollmentAutomation.Interval)
 	assert.Equal(t, 15*time.Minute, cfg.PendingRegistration.Interval)
+	assert.Equal(t, "registry.example.com/galaxy/game:{engine_version}", cfg.RuntimeManager.EngineImageTemplate)
 	assert.Equal(t, "galaxy-lobby-test", cfg.Telemetry.ServiceName)
 }
 
@@ -291,6 +294,34 @@ func TestEnrollmentAutomationConfigValidate(t *testing.T) {
 	require.ErrorContains(t, EnrollmentAutomationConfig{}.Validate(), "interval must be positive")
 }
 
+func TestRuntimeManagerConfigValidate(t *testing.T) {
+	t.Parallel()
+
+	require.NoError(t, RuntimeManagerConfig{EngineImageTemplate: "galaxy/game:{engine_version}"}.Validate())
+	require.ErrorContains(t,
+		RuntimeManagerConfig{EngineImageTemplate: ""}.Validate(),
+		"template must not be empty",
+	)
+	require.ErrorContains(t,
+		RuntimeManagerConfig{EngineImageTemplate: "galaxy/game:1.0.0"}.Validate(),
+		"placeholder",
+	)
+}
+
+func TestLoadFromEnvRejectsInvalidEngineImageTemplate(t *testing.T) {
+	clearAllEnv(t)
+	t.Setenv("LOBBY_REDIS_MASTER_ADDR", testRedisAddr)
+	t.Setenv("LOBBY_REDIS_PASSWORD", testRedisSecret)
+	t.Setenv("LOBBY_POSTGRES_PRIMARY_DSN", testDSN)
+	t.Setenv("LOBBY_USER_SERVICE_BASE_URL", testUserBaseURL)
+	t.Setenv("LOBBY_GM_BASE_URL", testGMBaseURL)
+	t.Setenv("LOBBY_ENGINE_IMAGE_TEMPLATE", "galaxy/game:no-placeholder")
+
+	_, err := LoadFromEnv()
+	require.Error(t, err)
+	require.Contains(t, err.Error(), "LOBBY_ENGINE_IMAGE_TEMPLATE")
+}
+
 func TestPendingRegistrationConfigValidate(t *testing.T) {
 	t.Parallel()
 
@@ -367,6 +398,7 @@ func clearAllEnv(t *testing.T) {
 		enrollmentAutomationIntervalEnvVar,
 		raceNameDirectoryBackendEnvVar,
 		raceNameExpirationIntervalEnvVar,
+		engineImageTemplateEnvVar,
 		otelServiceNameEnvVar,
 		otelTracesExporterEnvVar,
 		otelMetricsExporterEnvVar,