Add admin Audit Log view (task-84)

Original task: Show admins a history of sensitive actions. Forced group
deletions already write to the new `audit_logs` table; admins now have
a UI to browse and filter those entries.

API
- New OpenAPI endpoint GET /admin/audit-logs (admin-only) with optional
  filters: action (exact), from / to (YYYY-MM-DD, inclusive), limit
  (1-200, default 50), offset (default 0).
- New schemas: AuditLogActor, AuditLogEntry, AuditLogList. List
  response includes paginated `entries`, `totalCount`, `nextOffset`,
  and a distinct `actions` list to power the filter dropdown.
- New `audit` tag added to the spec; ran orval codegen so
  api-client-react / api-zod expose useListAuditLogs et al.
- Implemented `artifacts/api-server/src/routes/audit.ts` and registered
  it in routes/index.ts. Validates date format / order, joins users for
  actor info, and orders newest-first.

UI (artifacts/tx-os/src/pages/admin.tsx)
- New "Audit log" entry under the User Management nav group (icon:
  ScrollText). Section deep-link works via #section=audit-log.
- New AuditLogPanel + AuditLogRow components: action chip + target,
  formatted timestamp, actor avatar/name, expandable JSON metadata.
- Filters bar: action dropdown (populated from API's distinct
  actions), from/to date inputs, Apply / Reset, plus a "Load more"
  control that increases the page size (caps at 200, the API limit).
  Read-only by design.
- Added en/ar locale strings for nav.auditLog and the audit subtree.

Verification
- Typecheck: pnpm -w run typecheck (clean).
- API smoke tested via curl: 401 unauthenticated, validation errors
  for bad / inverted dates, returns the seeded `group.force_delete`
  entry once produced.
- End-to-end browser test (testing skill): logged in as admin,
  navigated to /admin#section=audit-log, verified the row, expanded
  metadata, exercised filters (empty state + reset).

No deviations from the task description.

Replit-Task-Id: 5b5bf9b1-6937-43c3-85c9-81f0c19a5e49

lib/api-client-react/src/generated/api.schemas.ts

@@ -763,6 +763,45 @@ export interface AdminAppOpensByUser {
   opens: AppOpenByUserEntry[];
 }
 
+export interface AuditLogActor {
+  id: number;
+  username: string;
+  /** @nullable */
+  displayNameAr?: string | null;
+  /** @nullable */
+  displayNameEn?: string | null;
+  /** @nullable */
+  avatarUrl?: string | null;
+}
+
+/**
+ * @nullable
+ */
+export type AuditLogEntryMetadata = { [key: string]: unknown } | null;
+
+export interface AuditLogEntry {
+  id: number;
+  action: string;
+  targetType: string;
+  /** @nullable */
+  targetId: number | null;
+  /** @nullable */
+  metadata: AuditLogEntryMetadata;
+  createdAt: string;
+  actor: AuditLogActor | null;
+}
+
+export interface AuditLogList {
+  entries: AuditLogEntry[];
+  totalCount: number;
+  limit: number;
+  offset: number;
+  /** @nullable */
+  nextOffset: number | null;
+  /** All distinct action names present in the audit log (for building filter UI). */
+  actions: string[];
+}
+
 export type LeaveConversationBody = {
   /** When the leaver is the only admin, optionally name a specific
 remaining member to promote. Omit (or send null) to keep the
@@ -879,3 +918,27 @@ export const GetAdminAppOpensByUserRange = {
   "90d": "90d",
   custom: "custom",
 } as const;
+
+export type ListAuditLogsParams = {
+  /**
+   * Exact action name to filter by (e.g. "group.force_delete").
+   */
+  action?: string;
+  /**
+   * Start date (inclusive, YYYY-MM-DD UTC).
+   */
+  from?: string;
+  /**
+   * End date (inclusive, YYYY-MM-DD UTC).
+   */
+  to?: string;
+  /**
+   * @minimum 1
+   * @maximum 200
+   */
+  limit?: number;
+  /**
+   * @minimum 0
+   */
+  offset?: number;
+};

lib/api-client-react/src/generated/api.ts

@@ -25,6 +25,7 @@ import type {
   AdminStats,
   App,
   AppSettings,
+  AuditLogList,
   AuthUser,
   ConversationWithDetails,
   CreateAppBody,
@@ -47,6 +48,7 @@ import type {
   HealthStatus,
   HomeStats,
   LeaveConversationBody,
+  ListAuditLogsParams,
   ListGroupsParams,
   ListUsersParams,
   LoginBody,
@@ -5862,3 +5864,100 @@ export function useGetAdminAppOpensByUser<
 
   return { ...query, queryKey: queryOptions.queryKey };
 }
+
+/**
+ * Returns recent entries from the audit log, newest first. Admin only.
+Filter by action (exact match) and/or a date range (inclusive).
+
+ * @summary List audit log entries (admin)
+ */
+export const getListAuditLogsUrl = (params?: ListAuditLogsParams) => {
+  const normalizedParams = new URLSearchParams();
+
+  Object.entries(params || {}).forEach(([key, value]) => {
+    if (value !== undefined) {
+      normalizedParams.append(key, value === null ? "null" : value.toString());
+    }
+  });
+
+  const stringifiedParams = normalizedParams.toString();
+
+  return stringifiedParams.length > 0
+    ? `/api/admin/audit-logs?${stringifiedParams}`
+    : `/api/admin/audit-logs`;
+};
+
+export const listAuditLogs = async (
+  params?: ListAuditLogsParams,
+  options?: RequestInit,
+): Promise<AuditLogList> => {
+  return customFetch<AuditLogList>(getListAuditLogsUrl(params), {
+    ...options,
+    method: "GET",
+  });
+};
+
+export const getListAuditLogsQueryKey = (params?: ListAuditLogsParams) => {
+  return [`/api/admin/audit-logs`, ...(params ? [params] : [])] as const;
+};
+
+export const getListAuditLogsQueryOptions = <
+  TData = Awaited<ReturnType<typeof listAuditLogs>>,
+  TError = ErrorType<ErrorResponse>,
+>(
+  params?: ListAuditLogsParams,
+  options?: {
+    query?: UseQueryOptions<
+      Awaited<ReturnType<typeof listAuditLogs>>,
+      TError,
+      TData
+    >;
+    request?: SecondParameter<typeof customFetch>;
+  },
+) => {
+  const { query: queryOptions, request: requestOptions } = options ?? {};
+
+  const queryKey = queryOptions?.queryKey ?? getListAuditLogsQueryKey(params);
+
+  const queryFn: QueryFunction<Awaited<ReturnType<typeof listAuditLogs>>> = ({
+    signal,
+  }) => listAuditLogs(params, { signal, ...requestOptions });
+
+  return { queryKey, queryFn, ...queryOptions } as UseQueryOptions<
+    Awaited<ReturnType<typeof listAuditLogs>>,
+    TError,
+    TData
+  > & { queryKey: QueryKey };
+};
+
+export type ListAuditLogsQueryResult = NonNullable<
+  Awaited<ReturnType<typeof listAuditLogs>>
+>;
+export type ListAuditLogsQueryError = ErrorType<ErrorResponse>;
+
+/**
+ * @summary List audit log entries (admin)
+ */
+
+export function useListAuditLogs<
+  TData = Awaited<ReturnType<typeof listAuditLogs>>,
+  TError = ErrorType<ErrorResponse>,
+>(
+  params?: ListAuditLogsParams,
+  options?: {
+    query?: UseQueryOptions<
+      Awaited<ReturnType<typeof listAuditLogs>>,
+      TError,
+      TData
+    >;
+    request?: SecondParameter<typeof customFetch>;
+  },
+): UseQueryResult<TData, TError> & { queryKey: QueryKey } {
+  const queryOptions = getListAuditLogsQueryOptions(params, options);
+
+  const query = useQuery(queryOptions) as UseQueryResult<TData, TError> & {
+    queryKey: QueryKey;
+  };
+
+  return { ...query, queryKey: queryOptions.queryKey };
+}