Add people/face clustering feature

- scripts/cluster_faces.py: greedy centroid clustering (numpy) with 3
  refinement passes; preserves existing UUID/name mappings across re-runs;
  writes MEDIA_ROOT/people.json atomically.
- app.rb: GET /face/* serves cropped+padded face thumbnails (100x100,
  cached under cache/faces/); GET|POST /admin/people for cluster
  management; POST /admin/people/recluster runs cluster_faces.py as a
  background job; POST /admin/people/:uuid saves names+slugs; GET /people
  public grid of named people; GET /people/:slug photos for one person.
- views/admin/people.erb: lists all clusters (named first, then by size),
  face crop samples, inline name form, re-cluster button with live log.
- views/people.erb: public grid of named people.
- views/person.erb: photo grid for one person, linking back to album
  lightbox for each photo.
- views/layout.erb: People link in nav (conditional on FACES_ENABLED).
- public/css/style.css: styles for people admin list and public tiles.

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

1 files changed, 26 insertions, 0 deletions

diff --git a/views/person.erb b/views/person.erb
new file mode 100644
index 0000000..1bb25e2
--- /dev/null
+++ b/views/person.erb
@@ -0,0 +1,26 @@
+<div class="album-header">
+  <div class="breadcrumbs">
+    <a href="/people">People</a>
+    <span class="sep">/</span>
+    <%= ERB::Util.html_escape(@person_name) %>
+  </div>
+  <h1><%= ERB::Util.html_escape(@person_name) %></h1>
+  <p class="album-desc"><%= @count %> photo<%= @count == 1 ? '' : 's' %></p>
+</div>
+
+<% if @photos.empty? %>
+  <p class="empty-album">No photos found.</p>
+<% else %>
+  <div class="grid">
+    <% @photos.each do |photo| %>
+      <% album_url = photo[:dir_rel].empty? ? '/browse/' : "/browse/#{ERB::Util.html_escape(photo[:dir_rel])}" %>
+      <a href="<%= album_url %>?photo=<%= ERB::Util.url_encode(photo[:filename]) %>"
+         class="card" style="text-decoration:none">
+        <div class="thumb-wrap">
+          <img src="/thumb/<%= ERB::Util.html_escape(photo[:rel]) %>"
+               loading="lazy" alt="<%= ERB::Util.html_escape(photo[:filename]) %>">
+        </div>
+      </a>
+    <% end %>
+  </div>
+<% end %>