Make headline images explicit, add asset credits

- related_assets gains a `headline` boolean (DB-enforced: at most one
  per page), replacing "first image by position" as the headline
  rule. A rake task backfills the current first image on every live
  head/draft, so nothing changes visually until an editor changes it.
- The image picker sidebar gets a star toggle reflecting the flag;
  the TinyMCE inline-image picker's badge now reads it too, instead
  of assuming position 0.
- No headline chosen (or none attached) now falls back to the
  gallery-count caption itself becoming the lightbox trigger, instead
  of the gallery being unreachable.
- Assets gain creator, source_url, and license_key (against a new
  config/asset_licenses.yml dictionary). asset_credit renders a
  degrading attribution line, reused as a hidden per-image glightbox
  caption so credit is one click away for every image, not only the
  headline's always-visible one.
- Fixed: asset thumbnails rendered unconditionally regardless of
  whether a real variant exists on disk. Asset#has_variant? checks
  file existence, not content type -- some legacy PDFs have real
  pre-rewrite thumbnails a content-type check would have hidden.
- assets#new/edit rebuilt onto the same node_description/node_content
  layout as assets#show, picking up the three new fields in the
  process.

6 files changed, 6 insertions, 0 deletions

diff --git a/app/views/custom/page_templates/public/chapter_detail.html.erb b/app/views/custom/page_templates/public/chapter_detail.html.erb
index c4c25982..18449b80 100644
--- a/app/views/custom/page_templates/public/chapter_detail.html.erb
+++ b/app/views/custom/page_templates/public/chapter_detail.html.erb
@@ -31,4 +31,5 @@
       </ul>
     </div>
   <% end %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
diff --git a/app/views/custom/page_templates/public/no_date_and_author.html.erb b/app/views/custom/page_templates/public/no_date_and_author.html.erb
index fa39e542..ec7e8501 100644
--- a/app/views/custom/page_templates/public/no_date_and_author.html.erb
+++ b/app/views/custom/page_templates/public/no_date_and_author.html.erb
@@ -3,6 +3,7 @@
   <p><%= sanitize( @page.abstract ) %></p>
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb b/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
index 64e2a7c3..c4866845 100644
--- a/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
+++ b/app/views/custom/page_templates/public/no_title_abstract_date_and_author.html.erb
@@ -1,6 +1,7 @@
 <div class="article" lang="<%= @page.effective_lang %>">
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/standard_template.html.erb b/app/views/custom/page_templates/public/standard_template.html.erb
index bbc8cd0c..e1e2eb08 100644
--- a/app/views/custom/page_templates/public/standard_template.html.erb
+++ b/app/views/custom/page_templates/public/standard_template.html.erb
@@ -3,6 +3,7 @@
   <div class="abstract"><p><%= sanitize( @page.abstract )%></p></div>
   <div id="headline_image"><%= headline_image %></div>
   <div class="body"><%= aggregate?(@page.body) %></div>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/title_only.html.erb b/app/views/custom/page_templates/public/title_only.html.erb
index 42fe9a64..d706e9dc 100644
--- a/app/views/custom/page_templates/public/title_only.html.erb
+++ b/app/views/custom/page_templates/public/title_only.html.erb
@@ -2,6 +2,7 @@
   <h2 class="headline"><%= @page.title %></h2>
   <div id="headline_image"><%= headline_image %></div>
   <%= aggregate?(@page.body) %>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>
diff --git a/app/views/custom/page_templates/public/update.html.erb b/app/views/custom/page_templates/public/update.html.erb
index d5995ace..0ff1bb24 100644
--- a/app/views/custom/page_templates/public/update.html.erb
+++ b/app/views/custom/page_templates/public/update.html.erb
@@ -4,6 +4,7 @@
   <div class="abstract"><p><%= sanitize( @page.abstract )%></p></div>
   <div id="headline_image"><%= headline_image %></div>
   <div class="body"><%= aggregate?(@page.body) %></div>
+  <%= render partial: 'content/asset_credits' %>
 </div>
 
 <%= will_paginate(@content_collection) if @content_collection %>