Secure Multi-Tenant Financial Reporting Microservice Architecture

Design a Laravel-based microservice for multi-tenant financial reporting that ensures absolute data isolation between different financial institutions. Implement robust tenant identification using cryptographic namespacing, implement role-based access control with granular permission sets, and create an auditable transaction log that captures every database mutation with immutable blockchain-like integrity checks. The solution must support concurrent transactions, handle complex financial data models, and provide real-time encryption at rest and in transit.