feat: per-task image/annotations, annotation editor toolbar, Tailwind compiled

- Add per-task file upload with image preview in task editor
- Add dedicated annotation editor page (task_drawing.html) with Fabric.js
- Add color picker, stroke width, and line dash controls to annotation toolbar
- Apply property changes to selected objects in real-time
- Disable style controls until a drawing tool or object is selected
- Remove zoom/pan from annotation toolbar (simplified UX)
- Auto-switch to select mode after placing annotation elements
- Show annotation overlay on task image previews (read-only canvas)
- Add file proxy route in measure blueprint for task file access
- Add file_path/file_type fields to TaskCreate/TaskUpdate Pydantic schemas
- Replace Tailwind CDN with compiled CSS (tailwind.config.js with full shades)
- Fix Alpine.js x-init crash: extract annotations JSON to <script> tags
  (recipe_preview.html, task_execute.html) to avoid HTML attribute breakage

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

client/templates/measure/task_execute.html

@@ -52,6 +52,9 @@
 {% endblock %}
 
 {% block content %}
+<script>
+  window.__taskAnnotations = {{ task.annotations_json|default('null')|tojson }};
+</script>
 <div class="min-h-[calc(100vh-3.5rem)] flex flex-col"
      x-data="taskExecute()"
      x-init="init()"
@@ -160,8 +163,8 @@
             <div class="annotation-container"
                  x-data="annotationViewer()"
                  x-init="
-                   imageUrl = '{{ url_for('static', filename='uploads/' ~ task.file_path) }}';
-                   annotations = {{ task.annotations_json|default('null')|tojson }};
+                   imageUrl = '/measure/api/files/{{ task.file_path }}';
+                   annotations = window.__taskAnnotations;
                    $nextTick(() => init());
                  "
                  x-effect="setActiveMarker(currentSubtask?.marker_number || 0)">
@@ -171,23 +174,18 @@
             </div>
 
             {% elif task.file_path and task.file_type == 'pdf' %}
-            {# PDF placeholder #}
-            <div class="annotation-container flex items-center justify-center">
-              <div class="text-center py-12">
-                <svg class="w-16 h-16 mx-auto text-red-400 mb-3" fill="none" stroke="currentColor" stroke-width="1" viewBox="0 0 24 24">
-                  <path stroke-linecap="round" stroke-linejoin="round" d="M7 21h10a2 2 0 002-2V9.414a1 1 0 00-.293-.707l-5.414-5.414A1 1 0 0012.586 3H7a2 2 0 00-2 2v14a2 2 0 002 2z"/>
-                </svg>
-                <p class="text-sm font-medium text-[var(--text-secondary)]">{{ _('Visualizzatore PDF') }}</p>
-                <p class="text-xs text-[var(--text-muted)] mt-1">{{ _('In fase di sviluppo') }}</p>
-                <a href="{{ url_for('static', filename='uploads/' ~ task.file_path) }}"
-                   target="_blank"
-                   class="btn btn-secondary mt-3 text-xs">
-                  <svg class="w-3.5 h-3.5" fill="none" stroke="currentColor" stroke-width="2" viewBox="0 0 24 24">
-                    <path stroke-linecap="round" stroke-linejoin="round" d="M10 6H6a2 2 0 00-2 2v10a2 2 0 002 2h10a2 2 0 002-2v-4M14 4h6m0 0v6m0-6L10 14"/>
-                  </svg>
-                  {{ _('Apri PDF') }}
-                </a>
-              </div>
+            {# PDF inline viewer using PDF.js via annotationViewer #}
+            <div class="annotation-container"
+                 x-data="annotationViewer()"
+                 x-init="
+                   imageUrl = '/measure/api/files/{{ task.file_path }}';
+                   annotations = window.__taskAnnotations;
+                   $nextTick(() => init());
+                 "
+                 x-effect="setActiveMarker(currentSubtask?.marker_number || 0)">
+              <canvas x-ref="annotationCanvas"
+                      @click="handleClick($event)"
+                      class="cursor-pointer"></canvas>
             </div>
 
             {% else %}
@@ -518,6 +516,10 @@
 {% endblock %}
 
 {% block extra_js %}
+<script src="https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.min.js"></script>
+<script>
+  pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/3.11.174/pdf.worker.min.js';
+</script>
 <script src="{{ url_for('static', filename='js/numpad.js') }}"></script>
 <script src="{{ url_for('static', filename='js/annotation-viewer.js') }}"></script>
 <script src="{{ url_for('static', filename='js/caliper.js') }}"></script>