fix: improve mutation telemetry error logging and diagnostics

Changes:
- Upgrade error logging from debug to warn level for better visibility
- Add diagnostic logging to track mutation processing
- Log telemetry disabled state explicitly
- Add context info (sessionId, intent, operationCount) to error logs
- Remove 'await' from telemetry calls to make them truly non-blocking

This will help identify why mutations aren't being persisted to the
workflow_mutations table despite successful workflow operations.

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

src/mcp/handlers-n8n-manager.ts

@@ -762,7 +762,7 @@ export async function handleUpdateWorkflow(
 
     // Track successful mutation
     if (workflowBefore) {
-      await trackWorkflowMutationForFullUpdate({
+      trackWorkflowMutationForFullUpdate({
         sessionId,
         toolName: 'n8n_update_full_workflow',
         userIntent,
@@ -771,7 +771,9 @@ export async function handleUpdateWorkflow(
         workflowAfter: workflow,
         mutationSuccess: true,
         durationMs: Date.now() - startTime,
-      }).catch(err => logger.debug('Failed to track mutation telemetry:', err));
+      }).catch(err => {
+        logger.warn('Failed to track mutation telemetry:', err);
+      });
     }
 
     return {
@@ -782,7 +784,7 @@ export async function handleUpdateWorkflow(
   } catch (error) {
     // Track failed mutation
     if (workflowBefore) {
-      await trackWorkflowMutationForFullUpdate({
+      trackWorkflowMutationForFullUpdate({
         sessionId,
         toolName: 'n8n_update_full_workflow',
         userIntent,
@@ -792,7 +794,9 @@ export async function handleUpdateWorkflow(
         mutationSuccess: false,
         mutationError: error instanceof Error ? error.message : 'Unknown error',
         durationMs: Date.now() - startTime,
-      }).catch(err => logger.debug('Failed to track mutation telemetry:', err));
+      }).catch(err => {
+        logger.warn('Failed to track mutation telemetry for failed operation:', err);
+      });
     }
 
     if (error instanceof z.ZodError) {

src/mcp/handlers-workflow-diff.ts

@@ -291,7 +291,7 @@ export async function handleUpdatePartialWorkflow(
 
       // Track successful mutation
       if (workflowBefore && !input.validateOnly) {
-        await trackWorkflowMutation({
+        trackWorkflowMutation({
           sessionId,
           toolName: 'n8n_update_partial_workflow',
           userIntent: input.intent || 'Partial workflow update',
@@ -300,7 +300,14 @@ export async function handleUpdatePartialWorkflow(
           workflowAfter: finalWorkflow,
           mutationSuccess: true,
           durationMs: Date.now() - startTime,
-        }).catch(err => logger.debug('Failed to track mutation telemetry:', err));
+        }).catch(err => {
+          logger.warn('Failed to track mutation telemetry:', err);
+          logger.debug('Mutation data that failed:', {
+            sessionId,
+            intent: input.intent,
+            operationCount: input.operations.length
+          });
+        });
       }
 
       return {
@@ -321,7 +328,7 @@ export async function handleUpdatePartialWorkflow(
     } catch (error) {
       // Track failed mutation
       if (workflowBefore && !input.validateOnly) {
-        await trackWorkflowMutation({
+        trackWorkflowMutation({
           sessionId,
           toolName: 'n8n_update_partial_workflow',
           userIntent: input.intent || 'Partial workflow update',
@@ -331,7 +338,9 @@ export async function handleUpdatePartialWorkflow(
           mutationSuccess: false,
           mutationError: error instanceof Error ? error.message : 'Unknown error',
           durationMs: Date.now() - startTime,
-        }).catch(err => logger.debug('Failed to track mutation telemetry:', err));
+        }).catch(err => {
+          logger.warn('Failed to track mutation telemetry for failed operation:', err);
+        });
       }
 
       if (error instanceof N8nApiError) {

src/telemetry/telemetry-manager.ts

@@ -153,13 +153,22 @@ export class TelemetryManager {
    */
   async trackWorkflowMutation(data: any): Promise<void> {
     this.ensureInitialized();
-    if (!this.isEnabled()) return;
+    if (!this.isEnabled()) {
+      logger.debug('Telemetry disabled, skipping mutation tracking');
+      return;
+    }
 
     this.performanceMonitor.startOperation('trackWorkflowMutation');
     try {
       const { mutationTracker } = await import('./mutation-tracker.js');
       const userId = this.configManager.getUserId();
 
+      logger.debug('Tracking workflow mutation', {
+        userId,
+        intent: data.userIntent?.substring(0, 50),
+        operationCount: data.operations?.length
+      });
+
       const mutationRecord = await mutationTracker.processMutation(data, userId);
 
       if (mutationRecord) {