Implement Treasury Service Layer and Business Logic

[GideonBature]

Treasury Service Layer and Business Logic Implementation

This PR implements a dedicated Treasury Service Layer that encapsulates core business logic for treasury operations in the BudgetChain Backend, as specified in issue #27. The implementation follows clean architecture principles with proper separation of concerns.

Features Implemented

1. Core Treasury Service Architecture

   • Implemented service classes for treasury operations, asset management, transactions, budgeting, and allocations
   • Created dedicated controllers with proper route definitions and role-based access control
   • Set up entity models with appropriate relationships and data validation

2. Asset Tracking and Management

   • Implemented TreasuryAssetService with methods for CRUD operations, balance management, and availability calculations
   • Added functionality for tracking asset allocations and remaining balances
   • Implemented asset type classification (cryptocurrency, token, NFT, fiat)

3. Budget Management Logic

   • Created budget lifecycle management with status transitions (draft, active, closed, expired)
   • Implemented budget validation, creation, approval, and closing processes
   • Added methods for calculating available and remaining budget amounts

4. Allocation Processing

   • Built allocation approval workflow with proper status transitions
   • Implemented disbursement processing with transaction tracking
   • Added validation to ensure allocations don't exceed budget or available asset balances

5. Transaction Recording and Processing

   • Created comprehensive transaction tracking for deposits, withdrawals, and internal transfers
   • Implemented blockchain transaction reference tracking with hash and block number
   • Added transaction status management (pending, confirmed, failed)

6. Treasury Overview and Reporting

   • Added methods for generating treasury overviews, risk metrics, and audit reports
   • Implemented transaction volume calculations
   • Created budget and allocation reporting endpoints

Technical Details

• Used BigNumber.js for precise financial calculations
• Implemented thread-safe database operations with transactions and proper locking
• Added comprehensive error handling with custom error types
• Set up Docker Compose configuration for PostgreSQL database
• Ensured proper data validation throughout the service layer

Closes #27

[anonfedora]

Merged. LFG

[GideonBature]

LFG!!!