Rationalized the default configuration file path and updated documentation

internal/config/config.go

@@ -14,7 +14,15 @@ import (
 	"gopkg.in/yaml.v3"
 )
 
-const DefaultConfigPath = "/etc/scriptorium/config.yml"
+const (
+	DefaultConfigPath      = "/etc/scriptorium/config.yml"
+	DefaultConfigPathLocal = "/usr/local/etc/scriptorium/config.yml"
+)
+
+var defaultConfigSearchPaths = []string{
+	DefaultConfigPathLocal,
+	DefaultConfigPath,
+}
 
 var (
 	ErrConfigNotFound    = errors.New("config file not found")
@@ -74,7 +82,24 @@ func LoadConfig(path string, explicit bool) (AppSettings, error) {
 	resolved := BuiltInDefaults()
 	configPath := strings.TrimSpace(path)
 	if configPath == "" {
-		configPath = DefaultConfigPath
+		if explicit {
+			configPath = DefaultConfigPath
+		} else {
+			for _, candidate := range defaultConfigSearchPaths {
+				if _, err := os.Stat(candidate); err == nil {
+					configPath = candidate
+					break
+				} else if !errors.Is(err, os.ErrNotExist) {
+					return AppSettings{}, fmt.Errorf("failed to stat config file %q: %w", candidate, err)
+				}
+			}
+		}
+	}
+	if configPath == "" {
+		if explicit {
+			return AppSettings{}, fmt.Errorf("%w: %s", ErrConfigNotFound, DefaultConfigPath)
+		}
+		return resolved, nil
 	}
 	configPath = filepath.Clean(configPath)