feat(templates): Add microformats2 h-feed and p-category markup for tags

Implement Phase 2 of v1.3.0 per microformats-tags-design.md

Template Updates:
- templates/index.html: Add h-feed properties (u-url, enhanced p-author with u-photo/p-note, feed-level u-photo)
- templates/index.html: Add p-category markup with rel="tag" to note previews
- templates/note.html: Add p-category markup with rel="tag" for tags
- templates/note.html: Enhance author h-card with u-photo and p-note (hidden for parsers)
- templates/note.html: Document u-photo placement outside e-content per draft spec
- templates/tag.html: Create new tag archive template with h-feed structure

Key Decisions Applied:
- Tags ordered alphabetically by display_name (ready for backend)
- rel="tag" on all p-category links per microformats2 spec
- Author bio (p-note) hidden with display: none for semantic parsing
- Dual u-photo elements intentional for parser compatibility
- Graceful fallback when author photo/bio not available

Templates are backward compatible and ready for backend integration.

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

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

templates/note.html

@@ -13,7 +13,8 @@
   <h1 class="p-name">{{ note.title }}</h1>
   {% endif %}
 
-  {# Media display at TOP (v1.2.0 Phase 3, per ADR-057) #}
+  {# u-photo placement: Per draft spec, u-photo must be direct child of h-entry, #}
+  {# NOT inside e-content. Media is rendered ABOVE e-content to meet this requirement. #}
   {{ display_media(note.media) }}
 
   {# e-content: note content BELOW media (per ADR-057) #}
@@ -36,14 +37,29 @@
     </span>
     {% endif %}
 
+    {# Tags / Categories #}
+    {# rel="tag" per microformats2 p-category specification #}
+    {% if note.tags %}
+    <div class="note-tags">
+      {% for tag in note.tags %}
+      <a class="p-category" rel="tag" href="{{ url_for('public.tag', tag=tag.name) }}">
+        {{ tag.display_name }}
+      </a>
+      {% endfor %}
+    </div>
+    {% endif %}
+
     {# Author h-card (nested within h-entry per Q20) #}
     {% if author %}
     <div class="p-author h-card">
+      {% if author.photo %}
+      <img class="u-photo" src="{{ author.photo }}" alt="{{ author.name or 'Author' }}" width="48" height="48">
+      {% endif %}
       <a class="p-name u-url" href="{{ author.url or author.me }}">
         {{ author.name or author.url or author.me }}
       </a>
-      {% if author.photo %}
-      <img class="u-photo" src="{{ author.photo }}" alt="{{ author.name or 'Author' }}" width="48" height="48">
+      {% if author.note %}
+      <span class="p-note" style="display: none;">{{ author.note }}</span>
       {% endif %}
     </div>
     {% endif %}