Save source descriptions, add "Why it's #N", fix IGDB studio names

Descriptions
- Items keep the source's description (TMDB/TheTVDB overview, IGDB
  summary, Wikipedia intro) in a new items.description column
  (migration 3); editable in the item form
- Deezer/MusicBrainz track counts and album names are now display-only
  hints, not saved as descriptions

Why it's #N
- The owner's note is presented as "Why it's #N" in the editor and the
  public detail view, above an "About" section with the description

IGDB developers
- IGDB credits internal divisions ("Nintendo EAD", "Nintendo EPD
  Production Group No. 8"). A developer whose name shares its first word
  with its parent company is credited to the parent ("Nintendo");
  independently named studios keep their name (Retro Studios, Naughty
  Dog, Landfall Games)
- Fall back to the publisher when IGDB lists no developer

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

web/static/js/public.js

@@ -38,7 +38,12 @@ function renderDialog(list, idx) {
       sub && h("p", { class: "dlg-sub" }, sub),
       it.badge && h("span", { class: "badge" }, it.badge),
       meta.length > 0 && h("dl", { class: "dlg-meta" }, meta.map((m) => [h("dt", {}, m.label), h("dd", {}, m.value)])),
-      it.note && h("blockquote", { class: "dlg-note" }, it.note),
+      it.note && h("section", { class: "dlg-why" },
+        h("h3", {}, `Why it's #${it.rank}`),
+        h("blockquote", { class: "dlg-note" }, it.note)),
+      it.description && h("section", { class: "dlg-about" },
+        h("h3", {}, "About"),
+        h("p", { class: "dlg-desc" }, it.description)),
       h("div", { class: "dlg-actions" },
         it.link && h("a", { class: "btn btn--sm", href: it.link, target: "_blank", rel: "noopener noreferrer" },
           icon("external"), it.source ? `View on ${it.source}` : "Learn more"),