fix: support camelCase property names from Indiekit Eleventy preset

The Indiekit Eleventy preset uses camelcaseKeys to convert frontmatter
properties (e.g., bookmark-of → bookmarkOf), but templates expected
underscore-separated names (bookmark_of).

Changes:
- Support both camelCase and underscore property names in all templates
- Update collections to filter on both property name formats
- Include interaction URLs (bookmarks, likes, replies, reposts) in
  Bridgy syndication content for proper social media posting

Fixes bookmark URLs not appearing on posts or in syndicated content.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

_includes/components/reply-context.njk

@@ -2,9 +2,15 @@
 {# Displays rich context for replies, likes, reposts, and bookmarks #}
 {# Uses h-cite microformat for citing external content #}
 
-{% if in_reply_to or like_of or repost_of or bookmark_of %}
+{# Support both camelCase (Indiekit Eleventy preset) and underscore (legacy) property names #}
+{% set replyTo = inReplyTo or in_reply_to %}
+{% set likedUrl = likeOf or like_of %}
+{% set repostedUrl = repostOf or repost_of %}
+{% set bookmarkedUrl = bookmarkOf or bookmark_of %}
+
+{% if replyTo or likedUrl or repostedUrl or bookmarkedUrl %}
 <aside class="reply-context p-4 mb-6 bg-surface-100 dark:bg-surface-800 rounded-lg border-l-4 border-primary-500">
-  {% if in_reply_to %}
+  {% if replyTo %}
   <div class="u-in-reply-to h-cite">
     <p class="text-sm text-surface-500 dark:text-surface-400 mb-2 flex items-center gap-2">
       <svg class="w-4 h-4" fill="none" stroke="currentColor" viewBox="0 0 24 24" aria-hidden="true">
@@ -12,13 +18,13 @@
       </svg>
       <span>In reply to:</span>
     </p>
-    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ in_reply_to }}">
-      {{ in_reply_to }}
+    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ replyTo }}">
+      {{ replyTo }}
     </a>
   </div>
   {% endif %}
 
-  {% if like_of %}
+  {% if likedUrl %}
   <div class="u-like-of h-cite">
     <p class="text-sm text-surface-500 dark:text-surface-400 mb-2 flex items-center gap-2">
       <svg class="w-4 h-4 text-red-500" fill="currentColor" viewBox="0 0 24 24" aria-hidden="true">
@@ -26,13 +32,13 @@
       </svg>
       <span>Liked:</span>
     </p>
-    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ like_of }}">
-      {{ like_of }}
+    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ likedUrl }}">
+      {{ likedUrl }}
     </a>
   </div>
   {% endif %}
 
-  {% if repost_of %}
+  {% if repostedUrl %}
   <div class="u-repost-of h-cite">
     <p class="text-sm text-surface-500 dark:text-surface-400 mb-2 flex items-center gap-2">
       <svg class="w-4 h-4 text-green-500" fill="none" stroke="currentColor" viewBox="0 0 24 24" aria-hidden="true">
@@ -40,13 +46,13 @@
       </svg>
       <span>Reposted:</span>
     </p>
-    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ repost_of }}">
-      {{ repost_of }}
+    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ repostedUrl }}">
+      {{ repostedUrl }}
     </a>
   </div>
   {% endif %}
 
-  {% if bookmark_of %}
+  {% if bookmarkedUrl %}
   <div class="u-bookmark-of h-cite">
     <p class="text-sm text-surface-500 dark:text-surface-400 mb-2 flex items-center gap-2">
       <svg class="w-4 h-4 text-yellow-500" fill="currentColor" viewBox="0 0 24 24" aria-hidden="true">
@@ -54,8 +60,8 @@
       </svg>
       <span>Bookmarked:</span>
     </p>
-    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ bookmark_of }}">
-      {{ bookmark_of }}
+    <a class="u-url font-medium text-primary-600 dark:text-primary-400 hover:underline break-all" href="{{ bookmarkedUrl }}">
+      {{ bookmarkedUrl }}
     </a>
   </div>
   {% endif %}

_includes/layouts/post.njk

@@ -26,10 +26,18 @@ withBlogSidebar: true
   </div>
 
   {# Bridgy syndication content - controls what gets posted to social networks #}
-  {# Uses description/summary if available, otherwise first 280 chars of content #}
+  {# For interaction types (bookmarks, likes, replies, reposts), include the target URL #}
+  {# Support both camelCase (Indiekit Eleventy preset) and underscore (legacy) property names #}
+  {% set bookmarkedUrl = bookmarkOf or bookmark_of %}
+  {% set likedUrl = likeOf or like_of %}
+  {% set replyTo = inReplyTo or in_reply_to %}
+  {% set repostedUrl = repostOf or repost_of %}
+
   {% set bridgySummary = description or summary or (content | ogDescription(280)) %}
-  {% if bridgySummary %}
-  <p class="p-summary e-bridgy-mastodon-content e-bridgy-bluesky-content hidden">{{ bridgySummary }}</p>
+  {% set interactionUrl = bookmarkedUrl or likedUrl or replyTo or repostedUrl %}
+
+  {% if bridgySummary or interactionUrl %}
+  <p class="p-summary e-bridgy-mastodon-content e-bridgy-bluesky-content hidden">{% if bookmarkedUrl %}🔖 {{ bookmarkedUrl }}{% if bridgySummary %} - {{ bridgySummary }}{% endif %}{% elif likedUrl %}❤️ {{ likedUrl }}{% if bridgySummary %} - {{ bridgySummary }}{% endif %}{% elif replyTo %}↩️ {{ replyTo }}{% if bridgySummary %} - {{ bridgySummary }}{% endif %}{% elif repostedUrl %}🔁 {{ repostedUrl }}{% if bridgySummary %} - {{ bridgySummary }}{% endif %}{% else %}{{ bridgySummary }}{% endif %}</p>
   {% endif %}
 
   <div class="e-content prose prose-surface dark:prose-invert max-w-none">