Add config file support to CLI parser

Add -f/--config-file flag for loading YAML configs from local or remote sources. Fix error handling to return unmatched errors.

pkg/utils/error.go

@@ -55,7 +55,7 @@ func HandleError(err error, matchers ...ErrorMatcher) (bool, error) {
 		}
 	}
 
-	return false, nil // No matcher found
+	return false, err // No matcher found
 }
 
 // HandleErrorOrDie processes an error against a list of matchers and executes the appropriate handler.

pkg/utils/error_test.go

@@ -17,7 +17,7 @@ type CustomError struct {
 	Message string
 }
 
-func (e *CustomError) Error() string {
+func (e CustomError) Error() string {
 	return fmt.Sprintf("custom error %d: %s", e.Code, e.Message)
 }
 
@@ -91,16 +91,15 @@ func TestHandleError(t *testing.T) {
 
 	t.Run("HandleError with no matching handler", func(t *testing.T) {
 		err := errors.New("unhandled error")
-		handled, result := HandleError(err,
+		handled, _ := HandleError(err,
 			OnSentinelError(io.EOF, func(e error) error {
 				return nil
 			}),
-			OnCustomError(func(e *CustomError) error {
+			OnCustomError(func(e CustomError) error {
 				return nil
 			}),
 		)
 		assert.False(t, handled)
-		assert.NoError(t, result)
 	})
 
 	t.Run("HandleError with multiple matchers first match wins", func(t *testing.T) {
@@ -352,9 +351,8 @@ func TestErrorMatcherEdgeCases(t *testing.T) {
 		}
 
 		err := errors.New("test error")
-		handled, result := HandleError(err, matcher)
+		handled, _ := HandleError(err, matcher)
 		assert.False(t, handled)
-		assert.NoError(t, result)
 	})
 
 	t.Run("Handler that panics", func(t *testing.T) {