feat: add internal stats flush API

internal/config/config.go

@@ -17,6 +17,7 @@ type Config struct {
 	Auth          AuthConfig
 	ModelRegistry ModelRegistryConfig
 	Quota         QuotaConfig
+	Internal      InternalConfig
 }
 
 type ServerConfig struct {
@@ -57,6 +58,10 @@ type QuotaConfig struct {
 	ResetIntervalSeconds int
 }
 
+type InternalConfig struct {
+	StatsToken string
+}
+
 func Load() (*Config, error) {
 	v := viper.New()
 
@@ -77,6 +82,7 @@ func Load() (*Config, error) {
 	v.SetDefault("model_registry.cache_dir", "./data/model-registry")
 	v.SetDefault("model_registry.timeout_seconds", 30)
 	v.SetDefault("quota.reset_interval_seconds", 300)
+	v.SetDefault("internal.stats_token", "")
 
 	v.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
 	v.AutomaticEnv()
@@ -98,6 +104,7 @@ func Load() (*Config, error) {
 	_ = v.BindEnv("model_registry.cache_dir", "EZ_MODEL_REGISTRY_CACHE_DIR")
 	_ = v.BindEnv("model_registry.timeout_seconds", "EZ_MODEL_REGISTRY_TIMEOUT_SECONDS")
 	_ = v.BindEnv("quota.reset_interval_seconds", "EZ_QUOTA_RESET_INTERVAL_SECONDS")
+	_ = v.BindEnv("internal.stats_token", "EZ_INTERNAL_STATS_TOKEN")
 
 	if configFile := os.Getenv("EZ_CONFIG_FILE"); configFile != "" {
 		v.SetConfigFile(configFile)
@@ -146,6 +153,9 @@ func Load() (*Config, error) {
 		Quota: QuotaConfig{
 			ResetIntervalSeconds: v.GetInt("quota.reset_interval_seconds"),
 		},
+		Internal: InternalConfig{
+			StatsToken: v.GetString("internal.stats_token"),
+		},
 	}
 
 	return cfg, nil