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/maker/recipe_preview.html

@@ -34,6 +34,14 @@
 {% endblock %}
 
 {% block content %}
+<script>
+  window.__taskAnnotations = {};
+  {% for task in recipe.tasks %}
+  {% if task.annotations_json %}
+  window.__taskAnnotations[{{ task.id }}] = {{ task.annotations_json|tojson }};
+  {% endif %}
+  {% endfor %}
+</script>
 <div class="container mx-auto px-4 sm:px-6 lg:px-8 py-8 max-w-5xl"
      x-data="recipePreview()"
      x-cloak>
@@ -208,7 +216,7 @@
                x-data="annotationViewer()"
                x-init="
                  imageUrl = '/maker/api/files/{{ task.file_path }}';
-                 annotations = {{ task.annotations_json|default('null')|tojson }};
+                 annotations = window.__taskAnnotations[{{ task.id }}] || null;
                  $nextTick(() => init());
                ">
             <canvas x-ref="annotationCanvas"></canvas>