perf: optimize workflow tool responses for token efficiency (v2.29.0) (#479)

* perf: optimize workflow tool responses for token efficiency (v2.29.0)

Reduce response sizes by 75-90% for 4 workflow management tools:

- n8n_update_partial_workflow: Returns {id, name, active, operationsApplied}
- n8n_create_workflow: Returns {id, name, active, nodeCount}
- n8n_update_full_workflow: Returns {id, name, active, nodeCount}
- n8n_delete_workflow: Returns {id, name, deleted: true}

AI agents can use n8n_get_workflow with mode 'structure' if they need
to verify the current workflow state after operations.

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update tests and add nodeCount to partial update response

- Fix handleCreateWorkflow test to expect minimal response
- Fix handleDeleteWorkflow test to expect minimal response
- Add nodeCount to n8n_update_partial_workflow response for consistency
- Update documentation and CHANGELOG

Conceived by Romuald Członkowski - https://www.aiadvisors.pl/en

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update handlers-workflow-diff tests for minimal response

Update 3 more tests that expected full workflow in response:
- should apply diff operations successfully
- should activate workflow after successful update
- should deactivate workflow after successful update

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

* fix: update integration tests to use minimal response format

Integration tests now verify minimal response format and use
client.getWorkflow() to fetch actual workflow state for verification.

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

* fix: update create/update workflow integration tests for minimal response

Integration tests now verify minimal response and use client.getWorkflow()
to fetch actual workflow state for detailed verification.

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

* fix: add type assertions to fix TypeScript errors in tests

Conceived by Romuald Czlonkowski - www.aiadvisors.pl/en

---------

Co-authored-by: Romuald Członkowski <romualdczlonkowski@MacBook-Pro-Romuald.local>
Co-authored-by: Claude <noreply@anthropic.com>

dist/mcp/handlers-n8n-manager.js

@@ -285,8 +285,13 @@ async function handleCreateWorkflow(args, context) {
         telemetry_1.telemetry.trackWorkflowCreation(workflow, true);
         return {
             success: true,
-            data: workflow,
-            message: `Workflow "${workflow.name}" created successfully with ID: ${workflow.id}`
+            data: {
+                id: workflow.id,
+                name: workflow.name,
+                active: workflow.active,
+                nodeCount: workflow.nodes?.length || 0
+            },
+            message: `Workflow "${workflow.name}" created successfully with ID: ${workflow.id}. Use n8n_get_workflow with mode 'structure' to verify current state.`
         };
     }
     catch (error) {
@@ -537,8 +542,13 @@ async function handleUpdateWorkflow(args, repository, context) {
         }
         return {
             success: true,
-            data: workflow,
-            message: `Workflow "${workflow.name}" updated successfully`
+            data: {
+                id: workflow.id,
+                name: workflow.name,
+                active: workflow.active,
+                nodeCount: workflow.nodes?.length || 0
+            },
+            message: `Workflow "${workflow.name}" updated successfully. Use n8n_get_workflow with mode 'structure' to verify current state.`
         };
     }
     catch (error) {
@@ -594,8 +604,12 @@ async function handleDeleteWorkflow(args, context) {
         const deleted = await client.deleteWorkflow(id);
         return {
             success: true,
-            data: deleted,
-            message: `Workflow ${id} deleted successfully`
+            data: {
+                id: deleted?.id || id,
+                name: deleted?.name,
+                deleted: true
+            },
+            message: `Workflow "${deleted?.name || id}" deleted successfully.`
         };
     }
     catch (error) {
@@ -682,7 +696,7 @@ async function handleValidateWorkflow(args, repository, context) {
     try {
         const client = ensureApiConfigured(context);
         const input = validateWorkflowSchema.parse(args);
-        const workflowResponse = await handleGetWorkflow({ id: input.id });
+        const workflowResponse = await handleGetWorkflow({ id: input.id }, context);
         if (!workflowResponse.success) {
             return workflowResponse;
         }