feat: Improve error handling with custom error types and detailed messages

config/errors.go

@@ -0,0 +1,28 @@
+package config
+
+import "fmt"
+
+// ConfigError represents a configuration error
+type ConfigError struct {
+	Param string
+	Err   error
+}
+
+func (e *ConfigError) Error() string {
+	return fmt.Sprintf("configuration error for %s: %v", e.Param, e.Err)
+}
+
+func (e *ConfigError) Unwrap() error {
+	return e.Err
+}
+
+// ValidationError represents a validation error
+type ValidationError struct {
+	Param  string
+	Value  string
+	Reason string
+}
+
+func (e *ValidationError) Error() string {
+	return fmt.Sprintf("invalid value '%s' for %s: %s", e.Value, e.Param, e.Reason)
+}