Add slideshow: root-level, shuffle, fullscreen, click-to-album

- Root slideshow: all_media_entries walks the full media tree so
  /slideshow/ shows every photo across all albums; Slideshow button
  always appears on the root album page
- Shuffle and Full screen checkboxes sit next to the Slideshow button
  on the album page; options pass as ?shuffle=1&fullscreen=1 URL params
- Fullscreen uses a tap-to-activate overlay (browsers block auto-entry
  on page load); webkit-prefixed for Safari; ⛶ button and F key for
  mid-session toggle
- Fullscreen mode hides controls, counter, caption bar, and site header
- Exiting fullscreen auto-pauses so the current photo stays visible
- Click/tap anywhere in the stage navigates to the photo's album
  lightbox; reads the live src attribute instead of ssIdx to avoid a
  race where ssIdx advances during the cross-fade while the old photo
  is still on screen
- layout.erb excluded from slideshow (layout: false) so the site header
  never appears there
- CSS cache-busted with ?v=2

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

1 files changed, 5 insertions, 3 deletions

diff --git a/views/album.erb b/views/album.erb
index 961b26a..c99ec3c 100644
--- a/views/album.erb
+++ b/views/album.erb
@@ -11,8 +11,10 @@
   <h1><%= @title %></h1>
   <% if @desc %><p class="album-desc"><%= @desc %></p><% end %>
   <div class="album-actions">
-    <% if @entries.any? { |e| %i[image video].include?(e[:type]) } %>
-      <a href="/slideshow/<%= @rel %>" class="btn">Slideshow</a>
+    <% if @rel.empty? ? @albums.any? : @entries.any? { |e| %i[image video].include?(e[:type]) } %>
+      <a href="/slideshow/<%= @rel %>" id="ss-launch" data-base="/slideshow/<%= @rel %>" class="btn">Slideshow</a>
+      <label class="ss-opt-label"><input type="checkbox" id="ss-opt-shuffle"> Shuffle</label>
+      <label class="ss-opt-label"><input type="checkbox" id="ss-opt-fullscreen"> Full screen</label>
     <% end %>
   </div>
 </div>
@@ -103,4 +105,4 @@ const ENTRIES = <%= @entries.map { |e|
   e.merge(src: "/media/#{file_rel}")
 }.to_json %>;
 </script>
-<script src="/js/album.js?v=2"></script>
+<script src="/js/album.js?v=3"></script>