feat: create profiling package + rewrite profiling tutorial

internal/config/bootstrap.go

@@ -80,24 +80,33 @@ func loadBootstrapDir(dir string) (map[store.ProxyName]BootstrapProxyConfig, err
 
 	proxies := make(map[store.ProxyName]BootstrapProxyConfig)
 	for _, f := range files {
-		data, err := os.ReadFile(f)
+		proxy, err := loadBootstrappedProxyConfig(f)
 		if err != nil {
-			return nil, errors.Wrapf(err, "could not read file '%s'", f)
-		}
-
-		proxy := BootstrapProxyConfig{}
-
-		if err := yaml.Unmarshal(data, &proxy); err != nil {
-			return nil, errors.Wrapf(err, "could not unmarshal proxy")
+			return nil, errors.Wrapf(err, "could not load proxy bootstrap file '%s'", f)
 		}
 
 		name := store.ProxyName(strings.TrimSuffix(filepath.Base(f), filepath.Ext(f)))
-		proxies[name] = proxy
+		proxies[name] = *proxy
 	}
 
 	return proxies, nil
 }
 
+func loadBootstrappedProxyConfig(filename string) (*BootstrapProxyConfig, error) {
+	data, err := os.ReadFile(filename)
+	if err != nil {
+		return nil, errors.Wrapf(err, "could not read file '%s'", filename)
+	}
+
+	proxy := BootstrapProxyConfig{}
+
+	if err := yaml.Unmarshal(data, &proxy); err != nil {
+		return nil, errors.Wrapf(err, "could not unmarshal proxy")
+	}
+
+	return &proxy, nil
+}
+
 func overrideProxies(base map[store.ProxyName]BootstrapProxyConfig, proxies map[store.ProxyName]BootstrapProxyConfig) map[store.ProxyName]BootstrapProxyConfig {
 	for name, proxy := range proxies {
 		base[name] = proxy

internal/config/environment.go

@@ -127,7 +127,7 @@ func (im *InterpolatedMap) UnmarshalYAML(value *yaml.Node) error {
 	return nil
 }
 
-func (im *InterpolatedMap) interpolateRecursive(data any) (any, error) {
+func (im InterpolatedMap) interpolateRecursive(data any) (any, error) {
 	switch typ := data.(type) {
 	case map[string]any:
 		for key, value := range typ {