fix: Placeholder field name mismatch + debug logging

Root Cause:
- PlaceholderPicker used q.id for signal placeholders
- Backend template context used question_type
- Placeholders never matched → empty values

Frontend PlaceholderPicker.jsx:
- Changed signal_${q.id} → signal_${q.type} (matches backend)
- Added question_${q.type} placeholders (question texts)
- New category: "Workflow - Questions"

Backend workflow_executor.py:
- Added extensive debug logging for template context
- Logs all signal_* and question_* keys + values
- Helps diagnose template rendering issues

Example:
- Question configured with type="kalorienbilanz"
- Frontend now shows: {{ node_4.signal_kalorienbilanz }}
- Frontend now shows: {{ node_4.question_kalorienbilanz }}
- Backend creates: template_context['node_4']['signal_kalorienbilanz']
- Should match and render correctly

Issue: Signal placeholders show empty values
Version: 0.9p (workflow module)
Part 3: End Node Template Engine - Field Name Fix

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/workflow_executor.py

@@ -624,6 +624,17 @@ def execute_end_node(
 
             logger.debug(f"End node {node.id}: Built template context for {len(template_context)} nodes")
 
+            # DEBUG: Log template context keys for each node
+            for node_id, node_ctx in template_context.items():
+                logger.info(f"End node template context[{node_id}]: {list(node_ctx.keys())}")
+                # Log signal keys specifically
+                signal_keys = [k for k in node_ctx.keys() if k.startswith('signal_')]
+                question_keys = [k for k in node_ctx.keys() if k.startswith('question_')]
+                if signal_keys:
+                    logger.info(f"  Signals: {signal_keys} → values: {[(k, node_ctx[k]) for k in signal_keys]}")
+                if question_keys:
+                    logger.info(f"  Questions: {question_keys} → values: {[(k, node_ctx[k]) for k in question_keys]}")
+
             # Render template
             try:
                 jinja_template = Template(node.template)

frontend/src/components/workflow/panels/PlaceholderPicker.jsx

@@ -372,17 +372,27 @@ function extractWorkflowPlaceholders(nodes) {
       })
     }
 
-    // Signals für Analysis Nodes mit Fragen
+    // Signals und Fragen für Analysis Nodes
     if (node.type === 'analysis' && node.data.questions && node.data.questions.length > 0) {
       node.data.questions.forEach((q, qIdx) => {
-        const questionId = q.id || `q${qIdx + 1}`
+        const questionType = q.type || `q${qIdx + 1}`
         const questionText = q.question || `Frage ${qIdx + 1}`
+
+        // Signal-Platzhalter (Antwort)
         placeholders.push({
-          placeholder: `{{ ${nodeId}.signal_${questionId} }}`,
+          placeholder: `{{ ${nodeId}.signal_${questionType} }}`,
           description: `${nodeLabel} - Signal: ${questionText.substring(0, 50)}${questionText.length > 50 ? '...' : ''}`,
           icon: '📊',
           category: 'Workflow - Signals'
         })
+
+        // Frage-Text-Platzhalter
+        placeholders.push({
+          placeholder: `{{ ${nodeId}.question_${questionType} }}`,
+          description: `${nodeLabel} - Frage-Text: ${questionText.substring(0, 50)}${questionText.length > 50 ? '...' : ''}`,
+          icon: '❓',
+          category: 'Workflow - Questions'
+        })
       })
     }
   })