feat(auth): role-based permissions + user management (plan phase 1)

Adds the RBAC foundation the CRUD phases build on, and the first write
module (users). The platform was read-only: every controller was guarded
only by AuthenticatedGuard and UserRole was ADMIN|STAFF. The old PHP app
stored level+role but enforced neither, so this is a fresh design.

Permission model (server-authoritative):
- UserRole expanded to an ordered rank ADMIN > MANAGER > STAFF > VIEWER.
  VIEWER is the read-only role; STAFF+ can write.
- auth/abilities.ts: ROLE_RANK + ABILITY_MIN matrix + can()/abilitiesFor().
- @RequireAbility decorator + AbilityGuard enforce it on write routes;
  reads stay on AuthenticatedGuard so any logged-in user can read.
- /auth/login and /auth/me now return the resolved abilities map, so the
  web gates its UI off one payload instead of duplicating the rules.

User management (ADMIN-only, ability "user:manage"):
- UsersService gains list/create/update/resetPassword (argon2), never
  returns passwordHash; blocks self-deactivation and self-demotion;
  maps duplicate email to 409.
- UsersController: GET/POST /users, PATCH /users/:id,
  POST /users/:id/reset-password.
- Every mutation logged via new AuditService over the existing
  ActivityLog model (global CommonModule).

Web:
- AuthContext + useAuth/useCan; AppShell provides the user and gates the
  new "Usuarios" nav entry on user:manage; shows the user's role.
- /usuarios admin page: list + create/edit form + password reset +
  active toggle, Spanish-first, reusing existing card/table/field styles.

Schema pushed to dev (enum only, non-destructive). Verified end-to-end
against dev: admin CRUD works, VIEWER writes 403 while reads 200,
self-lockout guards and duplicate-email 409 all hold.

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

apps/web/src/lib/api.ts

@@ -34,10 +34,12 @@ import type {
   PropertyListResponse,
   PropertySort,
   PropertyStats,
+  Role,
   ServiceKind,
   Statement,
   TransactionDomain,
   TrustFilter,
+  UserRow,
 } from "./types";
 
 export const API_ORIGIN =
@@ -341,3 +343,45 @@ export function getBankFacets(): Promise<BankFacets> {
 export function getBankSummary(year?: number): Promise<BankSummary> {
   return apiFetch<BankSummary>(`/bank/summary${year ? `?year=${year}` : ""}`);
 }
+
+/* ------------------------------------------------- Users / administration */
+
+export function listUsers(): Promise<UserRow[]> {
+  return apiFetch<UserRow[]>("/users");
+}
+
+export interface CreateUserInput {
+  name: string;
+  email: string;
+  password: string;
+  role: Role;
+  active?: boolean;
+}
+
+export function createUser(input: CreateUserInput): Promise<UserRow> {
+  return apiFetch<UserRow>("/users", {
+    method: "POST",
+    body: JSON.stringify(input),
+  });
+}
+
+export interface UpdateUserInput {
+  name?: string;
+  email?: string;
+  role?: Role;
+  active?: boolean;
+}
+
+export function updateUser(id: string, input: UpdateUserInput): Promise<UserRow> {
+  return apiFetch<UserRow>(`/users/${id}`, {
+    method: "PATCH",
+    body: JSON.stringify(input),
+  });
+}
+
+export function resetUserPassword(id: string, password: string): Promise<UserRow> {
+  return apiFetch<UserRow>(`/users/${id}/reset-password`, {
+    method: "POST",
+    body: JSON.stringify({ password }),
+  });
+}