Task #194: Show deleted user's full name in admin Audit Log

Original task
-------------
The admin Audit Log row for a user.delete entry showed
"Target: user #1234 · @ahmed" — i.e. the @username — even though
admins recognise people by name. Surface displayNameEn / displayNameAr
in that line and fall back to @username only when no display name
exists.

Backend
-------
artifacts/api-server/src/routes/users.ts
The user.delete handler already persists `displayNameEn` and
`displayNameAr` in audit metadata (added in commit eb7d15c). No
code change was needed on the API side. Verified the metadata
shape via the existing audit-log-coverage test.

Frontend
--------
artifacts/tx-os/src/pages/admin.tsx
- Renamed `forceDeletedEntityName` to `deletedEntityName` and
  updated the doc-comment.
- Relaxed its gate so it returns a name not only for force-delete
  entries but also for plain `user.delete` entries. Other delete
  actions (app.delete, group.delete) still gate on force-delete
  to avoid changing behaviour outside this task's scope.
- Updated the single call-site to use the new function name.

Effect: a non-force user.delete row now renders a "Target: user
#1234 · Ahmed Al-Saleh" line beneath the summary, with locale-aware
fallback (Ar -> En -> @username).

Verification
------------
- pnpm api-spec codegen + tx-os tsc --noEmit: clean.
- artifacts/api-server `node --test` for audit-log-coverage,
  audit-logs-actor-filter, audit-logs-forced-only-filter,
  audit-logs-target-filter: 43 / 43 tests pass (CSV export tests
  included).
- e2e test via runTest: created a user with displayName
  "Ahmed Test User" / "أحمد مستخدم", deleted without force,
  opened /#section=audit-log, and confirmed the new row's
  summary plus the secondary "Target: user #19630 · أحمد مستخدم"
  line render correctly (admin's Arabic locale was honoured).

Replit-Task-Id: fc3fc8f9-082a-49e4-b223-17baee11d268

artifacts/tx-os/src/pages/admin.tsx

@@ -6406,15 +6406,18 @@ function isForceDeleteEntry(entry: AuditLogEntry): boolean {
   return false;
 }
 
-// Pulls a human-readable display name for a force-deleted entity from its
-// audit metadata so the row can show "service #4821 · My Service" inline
-// without admins having to expand the JSON. Returns null when the row is not
-// a forced deletion or the metadata lacks any usable name field.
-function forceDeletedEntityName(
+// Pulls a human-readable display name for a deleted entity from its audit
+// metadata so the row can show "service #4821 · My Service" or "user #1234 ·
+// Ahmed Al-Saleh" inline without admins having to expand the JSON. Applies
+// to every force-delete row (where the dep counts are also useful) and to
+// non-force `user.delete` rows so admins can recognise the deleted person
+// by name even when the deletion was clean. Returns null when there is no
+// usable name field in the metadata.
+function deletedEntityName(
   entry: AuditLogEntry,
   lang: string,
 ): string | null {
-  if (!isForceDeleteEntry(entry)) return null;
+  if (!isForceDeleteEntry(entry) && entry.action !== "user.delete") return null;
   const meta = asRecord(entry.metadata);
   const en =
     asString(meta.nameEn) ??
@@ -6474,7 +6477,7 @@ function AuditLogRow({
   const summary = formatAuditSummary(entry, t, lang);
   const isForced = isForceDeleteEntry(entry);
   const chips = isForced ? dependencyChips(entry, t) : [];
-  const deletedName = forceDeletedEntityName(entry, lang);
+  const deletedName = deletedEntityName(entry, lang);
   const showDeletedTarget = deletedName != null && entry.targetId != null;
   return (
     <div