Add admin shard control: config, status, town crier (phase 5)

- admin/uoLink.controller.js: GET /admin/uo-link/config (masked config + live
  health + ingestion stats from the socket/broadcaster); PUT to save base/ws
  URL + write-only token + protocol + enabled, which (re)starts or stops the WS
  ingest client and activity-logs the change; POST/DELETE /uo-link/towncrier to
  publish/remove town-crier messages; GET /uo-link/stream (admin SSE channel,
  full feed incl. audit/cheat). Mounted adminOnly with express-validator guards
  + #swagger annotations (new "Admin · Shard" tag, TownCrierRequest schema).
- server.js: startup probe (checkUoLink) that logs reachability and warns
  loudly on a protocol mismatch when the integration is enabled.
- client: api.admin uo-link methods; ShardAdmin.jsx control panel (status
  panel with ingestion stats, config form, town crier) modeled on
  DiscordBotAdmin; wired into AdminLayout nav/titles + the /admin/shard route.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_011qPmpmVH1xGCiZoz9m9vW3

client/src/App.jsx

@@ -34,6 +34,7 @@ import SettingsAdmin from './routes/admin/views/SettingsAdmin.jsx'
 import ActivityAdmin from './routes/admin/views/ActivityAdmin.jsx'
 import BotActivityAdmin from './routes/admin/views/BotActivityAdmin.jsx'
 import DiscordBotAdmin from './routes/admin/views/DiscordBotAdmin.jsx'
+import ShardAdmin from './routes/admin/views/ShardAdmin.jsx'
 import AuthProvidersAdmin from './routes/admin/views/AuthProvidersAdmin.jsx'
 import UsersAdmin from './routes/admin/views/UsersAdmin.jsx'
 import AccountAdmin from './routes/admin/views/AccountAdmin.jsx'
@@ -111,6 +112,7 @@ export default function App() {
             <Route path="activity" element={<ActivityAdmin />} />
             <Route path="bot-activity" element={<BotActivityAdmin />} />
             <Route path="discord-bot" element={<DiscordBotAdmin />} />
+            <Route path="shard" element={<ShardAdmin />} />
             <Route path="auth-providers" element={<AuthProvidersAdmin />} />
             <Route path="users" element={<UsersAdmin />} />
             <Route path="account" element={<AccountAdmin />} />