Add otel tracer

Signed-off-by: Asai Neko <sugar@sne.moe>

config/types.go

@@ -9,6 +9,7 @@ type config struct {
 	Secrets  secrets  `yaml:"secrets"`
 	TTL      ttl      `yaml:"ttl"`
 	KYC      kyc      `yaml:"kyc"`
+	Tracer   tracer   `yaml:"tracer"`
 }
 
 type server struct {
@@ -65,3 +66,7 @@ type kyc struct {
 	AliAccessKeyId     string `yaml:"ali_access_key_id"`
 	AliAccessKeySecret string `yaml:"ali_access_key_secret"`
 }
+
+type tracer struct {
+	OtelControllerEndpoint string `yaml:"otel_controller_endpoint"`
+}