feat(admin): view a user's shard footprint at /admin/users/:id

Add a "View" action beside Edit in the users table that opens a dedicated,
read-only page showing everything the uo-link shard knows about a user,
scoped to their linked game accounts: character rosters, currently-online
characters, houses (IDOC-first), and recent vendor sales.

Backend (admin-only, under the existing /users adminOnly gate):
- GET /admin/users/:id — single sanitized user (page is deep-linkable)
- GET /admin/users/:id/shard/{accounts,sales,houses,online}
- shardState: listHousesByAccounts / listOnlineByAccounts (+ model shapers)
- Extract salesForAccounts into utils/shardSales; reuse in player getSales
- Live rosters reuse the existing admin-bypass /admin/shard/* endpoints,
  so no new routes for roster/vendors/char

Frontend:
- UserDetail page reusing CharacterStats / GameAccounts / VendorSales
- GameAccounts gains a readOnly prop (drops link form + self-voice copy)
- api.admin.getUser + api.admin.userShard(id) scope; route + layout title

Tests: adminUserShard.test.js (404, account scoping, empty accounts,
salesForAccounts cap/filter). Full server suite 164 pass; client builds.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0114TpmrNW4wNXsHq5CR72jQ

client/src/components/GameAccounts.jsx

@@ -5,7 +5,9 @@ import { Loading, ErrorState } from './PageState.jsx'
 // Shared game-account linking + character roster, used by both the player portal
 // (/player) and the staff account page (/admin/account). `scope` is the api
 // object with { link, accounts, roster } (player or admin self-service); `charTo`
-// maps a serial to the route for that character's sheet.
+// maps a serial to the route for that character's sheet. `readOnly` drops the
+// link forms and self-voice copy for the admin case where staff view *another*
+// user's accounts (no `scope.link`) at /admin/users/:id.
 
 function LinkForm({ scope, onLinked, compact }) {
   const [code, setCode] = useState('')
@@ -105,7 +107,7 @@ function AccountRoster({ scope, account, charTo }) {
   )
 }
 
-export default function GameAccounts({ scope, charTo }) {
+export default function GameAccounts({ scope, charTo, readOnly = false }) {
   const [accounts, setAccounts] = useState(null)
   const [error, setError] = useState('')
 
@@ -114,16 +116,26 @@ export default function GameAccounts({ scope, charTo }) {
     try {
       setAccounts(await scope.accounts())
     } catch {
-      setError('Could not load your game accounts.')
+      setError(readOnly ? 'Could not load this user’s game accounts.' : 'Could not load your game accounts.')
     }
-  }, [scope])
+  }, [scope, readOnly])
   useEffect(() => { load() }, [load])
 
   if (error) return <ErrorState message={error} />
   if (!accounts) return <Loading />
 
-  // Not linked yet — prompt to link.
+  // No linked accounts. In read-only (admin viewing another user) this is just an
+  // empty state; otherwise it's the link-your-account prompt.
   if (accounts.length === 0) {
+    if (readOnly) {
+      return (
+        <div className="panel" style={{ padding: 22 }}>
+          <p className="sans dim" style={{ margin: 0, fontSize: '0.88rem' }}>
+            This user has not linked a game account.
+          </p>
+        </div>
+      )
+    }
     return (
       <div className="panel" style={{ padding: 22 }}>
         <div className="field-label" style={{ marginBottom: 8 }}>Link your game account</div>
@@ -147,10 +159,12 @@ export default function GameAccounts({ scope, charTo }) {
           <AccountRoster scope={scope} account={a.account} charTo={charTo} />
         </section>
       ))}
-      <section style={{ borderTop: '1px solid var(--line-soft)', paddingTop: 20 }}>
-        <div className="field-label" style={{ marginBottom: 10 }}>Link another account</div>
-        <LinkForm scope={scope} onLinked={load} compact />
-      </section>
+      {!readOnly && (
+        <section style={{ borderTop: '1px solid var(--line-soft)', paddingTop: 20 }}>
+          <div className="field-label" style={{ marginBottom: 10 }}>Link another account</div>
+          <LinkForm scope={scope} onLinked={load} compact />
+        </section>
+      )}
     </div>
   )
 }