Audit_Firm_v2.0.3.1

Phase: Scope Hardening

Key additions:
- Scope guard utilities for tenant and branch validation
- Intended to be used by IAM, RBAC and System Settings modules
- Prevents cross-tenant and cross-branch operations

Next planned phases:
v2.0.3.2  Permission Guards
v2.0.3.4  Audit Trail
v2.0.3.4  User Lifecycle Controls
v2.0.3.5  Invite / Password Reset Flows
v2.0.3.6  Service Layer Refactor + UI Improvements