fix: implement layer-based error wrapping strategy

Remove redundant error wrapping to prevent message duplication while
maintaining error chains for proper error inspection.

Changes:
- Entry point layer (cmd/): Pass through all errors
- Orchestration layer (deploy/delete/describe/validate): Pass through
  errors from lower layers
- Business logic layer (resolve/): Pass through config and file system
  errors that already have full context
- Update tests to verify actual error messages from boundary layers

Before: failed to resolve stack dependencies: failed to get stack vpc:
        failed to resolve stack 'vpc' for context 'dev': stack 'vpc'
        not found in configuration

After:  failed to resolve stack 'vpc' for context 'dev': stack 'vpc'
        not found in configuration

This implements ADR 0023 layer-based error wrapping strategy.

Author: orien

cmd/describe.go

@@ -72,7 +72,7 @@ func describeSingleStack(ctx context.Context, stackName, contextName, configFile
 	// Resolve the target stack configuration
 	stack, err := resolver.ResolveStack(ctx, contextName, stackName)
 	if err != nil {
-		return fmt.Errorf("failed to resolve stack %s: %w", stackName, err)
+		return err
 	}
 
 	// Get describer instance
@@ -81,7 +81,7 @@ func describeSingleStack(ctx context.Context, stackName, contextName, configFile
 	// Retrieve stack information from AWS
 	stackDesc, err := d.DescribeStack(ctx, stack)
 	if err != nil {
-		return fmt.Errorf("failed to describe stack %s: %w", stackName, err)
+		return err
 	}
 
 	// Format and display the information

cmd/describe_test.go

@@ -234,7 +234,7 @@ stacks:
 
 	// Verify error handling
 	assert.Error(t, err, "describe command should return error when describer fails")
-	assert.Contains(t, err.Error(), "failed to describe stack nonexistent-stack")
+	assert.Contains(t, err.Error(), "stack not found")
 
 	// Verify mock expectations
 	mockDescriber.AssertExpectations(t)
@@ -257,7 +257,7 @@ func TestDescribeCommand_HandlesResolverError(t *testing.T) {
 
 	// Verify error handling
 	assert.Error(t, err, "describe command should return error when resolver fails")
-	assert.Contains(t, err.Error(), "failed to resolve stack")
+	assert.Contains(t, err.Error(), "failed to read config file")
 
 	// Verify no describer calls were made since resolver failed
 	mockDescriber.AssertNotCalled(t, "DescribeStack")

cmd/diff.go

@@ -74,7 +74,7 @@ func diffSingleStack(ctx context.Context, stackName, contextName, configFile str
 	// Resolve the target stack
 	targetStack, err := resolver.ResolveStack(ctx, contextName, stackName)
 	if err != nil {
-		return fmt.Errorf("failed to resolve stack %s: %w", stackName, err)
+		return err
 	}
 
 	// Create diff options based on command flags
@@ -90,7 +90,7 @@ func diffSingleStack(ctx context.Context, stackName, contextName, configFile str
 	// Perform the diff
 	result, err := d.DiffStack(ctx, targetStack, options)
 	if err != nil {
-		return fmt.Errorf("failed to diff stack %s: %w", stackName, err)
+		return err
 	}
 
 	// Output the results using plain text

internal/delete/deleter.go

@@ -123,7 +123,7 @@ func (d *StackDeleter) DeleteSingleStack(ctx context.Context, stackName, context
 	// Resolve single stack
 	stack, err := d.resolver.ResolveStack(ctx, contextName, stackName)
 	if err != nil {
-		return fmt.Errorf("failed to resolve stack dependencies: %w", err)
+		return err
 	}
 
 	return d.deleteStackWithFeedback(ctx, stack, contextName)
@@ -134,7 +134,7 @@ func (d *StackDeleter) DeleteAllStacks(ctx context.Context, contextName string)
 	// Get list of stacks to delete
 	stackNames, err := d.configProvider.ListStacks(contextName)
 	if err != nil {
-		return fmt.Errorf("failed to get stacks for context %s: %w", contextName, err)
+		return err
 	}
 	if len(stackNames) == 0 {
 		fmt.Printf("No stacks found in context %s\n", contextName)
@@ -144,7 +144,7 @@ func (d *StackDeleter) DeleteAllStacks(ctx context.Context, contextName string)
 	// Get dependency order without resolving stacks
 	deploymentOrder, err := d.resolver.GetDependencyOrder(contextName, stackNames)
 	if err != nil {
-		return fmt.Errorf("failed to calculate dependency order: %w", err)
+		return err
 	}
 
 	// Reverse the deployment order for safe deletion
@@ -159,7 +159,7 @@ func (d *StackDeleter) DeleteAllStacks(ctx context.Context, contextName string)
 		// Resolve this specific stack
 		stack, err := d.resolver.ResolveStack(ctx, contextName, stackName)
 		if err != nil {
-			return fmt.Errorf("failed to resolve stack %s: %w", stackName, err)
+			return err
 		}
 
 		err = d.deleteStackWithFeedback(ctx, stack, contextName)

internal/delete/deleter_test.go

@@ -276,7 +276,7 @@ func TestDeleteSingleStack_ResolverFailure(t *testing.T) {
 
 	// Assertions
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to resolve stack dependencies")
+	assert.Contains(t, err.Error(), "stack not found")
 	mockResolver.AssertExpectations(t)
 }
 
@@ -408,7 +408,7 @@ func TestDeleteAllStacks_ListStacksFailure(t *testing.T) {
 
 	// Assertions
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to get stacks for context dev")
+	assert.Contains(t, err.Error(), "context not found")
 	mockConfigProvider.AssertExpectations(t)
 }
 
@@ -431,7 +431,7 @@ func TestDeleteAllStacks_GetDependencyOrderFailure(t *testing.T) {
 
 	// Assertions
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to calculate dependency order")
+	assert.Contains(t, err.Error(), "circular dependency")
 	mockConfigProvider.AssertExpectations(t)
 	mockResolver.AssertExpectations(t)
 }
@@ -458,7 +458,7 @@ func TestDeleteAllStacks_ResolveStackFailure(t *testing.T) {
 
 	// Assertions
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to resolve stack vpc")
+	assert.Contains(t, err.Error(), "stack resolution failed")
 	mockConfigProvider.AssertExpectations(t)
 	mockResolver.AssertExpectations(t)
 }

internal/deploy/deployer.go

@@ -341,7 +341,7 @@ func (d *StackDeployer) DeploySingleStack(ctx context.Context, stackName, contex
 	// Resolve single stack
 	stack, err := d.resolver.ResolveStack(ctx, contextName, stackName)
 	if err != nil {
-		return fmt.Errorf("failed to resolve stack dependencies: %w", err)
+		return err
 	}
 
 	return d.deployStackWithFeedback(ctx, stack, contextName)
@@ -370,7 +370,7 @@ func (d *StackDeployer) DeployAllStacks(ctx context.Context, contextName string)
 		// Resolve this specific stack to get fresh parameter values
 		stack, err := d.resolver.ResolveStack(ctx, contextName, stackName)
 		if err != nil {
-			return fmt.Errorf("failed to resolve stack %s: %w", stackName, err)
+			return err
 		}
 
 		err = d.deployStackWithFeedback(ctx, stack, contextName)

internal/deploy/deployer_test.go

@@ -164,7 +164,6 @@ func TestDeploySingleStack_ResolverError(t *testing.T) {
 
 	// Verify error is propagated correctly
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to resolve stack dependencies")
 	assert.Contains(t, err.Error(), "config load failed")
 
 	mockProvider.AssertExpectations(t)
@@ -201,7 +200,6 @@ func TestDeployAllStacks_ConfigLoadError(t *testing.T) {
 
 	// Should fail during config loading for individual stack resolution
 	assert.Error(t, err)
-	assert.Contains(t, err.Error(), "failed to resolve stack")
 	assert.Contains(t, err.Error(), "config resolution failed")
 
 	mockProvider.AssertExpectations(t)

internal/describe/describer.go

@@ -36,7 +36,7 @@ func (d *StackDescriber) DescribeStack(ctx context.Context, stack *model.Stack)
 	// Use existing AWS operations to get stack information
 	stackInfo, err := cfOps.DescribeStack(ctx, stack.Name)
 	if err != nil {
-		return nil, fmt.Errorf("failed to describe stack %s: %w", stack.Name, err)
+		return nil, err
 	}
 
 	// Convert AWS StackInfo to our StackDescription format

internal/describe/describer_test.go

@@ -127,7 +127,6 @@ func TestStackDescriber_DescribeStack_AWSError(t *testing.T) {
 	// Verify
 	assert.Error(t, err, "DescribeStack should return error when AWS operations fail")
 	assert.Nil(t, result, "Result should be nil on error")
-	assert.Contains(t, err.Error(), "failed to describe stack failing-stack")
 	assert.Contains(t, err.Error(), "AWS CloudFormation error: stack not found")
 
 	mockCFOps.AssertExpectations(t)

internal/resolve/stack_resolver.go

@@ -54,19 +54,19 @@ func (r *StackResolver) ResolveStack(ctx context.Context, context string, stackN
 	// Load configuration
 	cfg, err := r.configProvider.LoadConfig(ctx, context)
 	if err != nil {
-		return nil, fmt.Errorf("failed to load config: %w", err)
+		return nil, err
 	}
 
 	// Get stack configuration
 	stackConfig, err := r.configProvider.GetStack(stackName, context)
 	if err != nil {
-		return nil, fmt.Errorf("failed to get stack %s: %w", stackName, err)
+		return nil, err
 	}
 
 	// Read raw template content
 	rawTemplate, err := r.fileSystemResolver.Resolve(stackConfig.Template)
 	if err != nil {
-		return nil, fmt.Errorf("failed to read template: %w", err)
+		return nil, err
 	}
 
 	// Process template with variables (parameters and context)