feat(sites): on-demand site detail page content (INT-2)

- SiteReleaseDetail.page: description, MediaInfo/BDInfo, screenshots,
  IMDb / Douban / TMDB ids, file list, tags, uploader, plus a parse probe
  (labels found) for layout-change diagnosis. Generic NexusPHP rules
  (field label -> next sibling) starting from the MovieClaw detail
  selectors; site overrides under umt.detail.page (HHClub: div labels).
  M-Team builds the same structure from descr BBCode + mediainfo.
- Fetched only on demand (drawer open without cache, "复核详情",
  release.inspect); content in kv_cache region site.detail for the
  site detail cache period (>= 24 h); within the window the site is not
  requested again. External ids persist in source_release.raw._detail,
  which list snapshots do not overwrite.
- Screenshots only as proxy paths /api/v1/img/site-detail/{rid}/{i}:
  public-address check on every hop, no site credentials, magic-byte
  image check, 8 MB cap. Poster proxy shares the same helper.
- Identity: site ids count as explicit-id evidence; when TMDB is
  queried, a TMDB id goes straight to details and an IMDb id to
  /find (no title search on a hit). Douban only for local recall.
- Release drawer "站点详情页" section; fixtures and tests for HHClub div
  layout, rowhead layout, BBCode, cache/proxy/identity end to end.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/testkit/src/sites/mock-nexusphp.ts

@@ -144,7 +144,7 @@ function detailBody(r: MockNexusRelease): string {
 <tr><td class="rowhead">副标题</td><td class="rowfollow" align="left">${esc(r.subtitle ?? "")}</td></tr>
 <tr><td class="rowhead">基本信息</td><td class="rowfollow" align="left"><b>大小：</b>${esc(r.sizeText)}&nbsp;&nbsp;&nbsp;<b>类型:</b> ${esc(r.catName)}&nbsp;&nbsp;发布于 <span title="${r.uploadedAt}">${esc(r.relativeTime ?? r.uploadedAt)}</span></td></tr>
 <tr><td class="rowhead">同伴</td><td class="rowfollow" align="left">${r.seeders.replace(/,/g, "")}个做种者 | ${r.leechers.replace(/,/g, "")}个下载者</td></tr>
-<tr><td class="rowhead">简介</td><td class="rowfollow" align="left"><div id="kdescr">${esc(r.description ?? "暂无简介")}</div></td></tr>
+<tr><td class="rowhead">简介</td><td class="rowfollow" align="left"><div id="kdescr">${r.descriptionHtml ?? esc(r.description ?? "暂无简介")}</div></td></tr>
 </table>`;
 }