feat(news): auto-push published news to the in-game Town Cryer News gump (2.1)

Phase 4: sync the site's published news posts into the Protocol 2.1 News gump.

- uoLinkClient.postNews / deleteNews.
- utils/newsGump.js — a STATE SYNC (not a one-shot announce leg): an article
  stays in the gump while its post is published news and is pulled when it leaves
  that state. buildArticle renders a compact gump-HTML block (centred title +
  plain-text excerpt — the gump supports only a small HTML subset) with a
  "more info" link to /site/news and an optional gump image from the
  `news_gump_image` setting. Every call is best-effort / never-throws.
- Hooked into the posts pipeline alongside the existing announce enqueue:
  syncPost on create/update/publish (fresh publish announces; edits refresh
  silently; leaving published-news pulls the article), removePost on delete.
- reassertAll() runs in uoLinkSocket.backfill on every WS (re)connect —
  reconciles the gump to our source of truth and recovers any article whose
  original live push failed (silent, so a reconnect never re-proclaims old news).

Server 185/185, swagger regenerated. Refs .plans/protocol2-integration.md (Phase 4).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

server/src/utils/uoLinkClient.js

@@ -118,6 +118,13 @@ const postTownCrier = ({ id, lines, durationSec }) =>
   call('/towncrier', { method: 'POST', body: { id, lines, durationSec } })
 const deleteTownCrier = (id) => call(`/towncrier/${encodeURIComponent(id)}`, { method: 'DELETE' })
 
+// Town Cryer News gump (Protocol 2.1). A full article (title/HTML body/image/URL)
+// in the in-game News window; re-posting the same id REPLACES it. `announce`
+// (default true on the sidecar) controls whether the criers proclaim the title.
+const postNews = ({ id, title, body, image, url, announce }) =>
+  call('/news', { method: 'POST', body: { id: String(id), title, body, image, url, announce } })
+const deleteNews = (id) => call(`/news/${encodeURIComponent(id)}`, { method: 'DELETE' })
+
 // ── Staff write plane (§6) ─────────────────────────────────────────────────
 // Every call carries `actor` — the website username of the staff member — set by
 // the controller from the session, NEVER from the browser. The shard records it
@@ -155,6 +162,8 @@ module.exports = {
   linkLookup,
   postTownCrier,
   deleteTownCrier,
+  postNews,
+  deleteNews,
   adminKick,
   adminBan,
   adminUnban,