Add comprehensive documentation and unit tests

Documentation:
- Add detailed README files for all services (auth, character, database, launcher, packet, utils, world)
- Create API documentation for the database service with detailed endpoint specifications
- Document database schema and relationships
- Add service architecture overviews and configuration instructions

Unit Tests:
- Implement comprehensive test suite for database repositories (user, character, session)
- Add gRPC service tests for database interactions
- Create tests for packet service components (bufferpool, connection, packets)
- Add utility service tests (health check, logging, load balancer, redis cache, service discovery)
- Implement auth service user tests
- Add character service tests

Code Structure:
- Reorganize test files into a more consistent structure
- Create a dedicated tests crate for integration testing
- Add test helpers and mock implementations for easier testing

README.md

@@ -1,2 +1,111 @@
-# osirose-new
+# MMORPG Server Architecture
 
+A microservice-based server architecture for an MMORPG game, built with Rust.
+
+## Overview
+
+This project implements a complete server infrastructure for an MMORPG game, using a microservice architecture for scalability and maintainability. Each service is responsible for a specific domain of the game, communicating with other services via gRPC.
+
+## Architecture
+
+The server architecture consists of the following microservices:
+
+### Core Services
+
+- **Auth Service**: Handles user authentication, session validation, and account management
+- **Character Service**: Manages character creation, deletion, and retrieval
+- **Database Service**: Provides centralized database access for all services
+- **Packet Service**: Handles game client communication via custom binary packets
+- **World Service**: Manages game world state and character interactions
+
+### Support Components
+
+- **Utils**: Shared utilities used by all services
+- **Launcher**: Client-side launcher for the game
+
+## Communication Flow
+
+1. **Client → Launcher**: User launches the game via the launcher
+2. **Launcher → Packet Service**: Game client connects to the packet service
+3. **Packet Service → Auth Service**: Validates user session
+4. **Packet Service → Character Service**: Retrieves character data
+5. **Packet Service → World Service**: Manages game world interactions
+
+## Technologies
+
+- **Language**: Rust
+- **Communication**: gRPC, custom binary protocol
+- **Database**: PostgreSQL (managed by external system)
+- **Caching**: Redis
+- **Service Discovery**: Kubernetes DNS, Consul
+- **Metrics**: Prometheus
+
+## External Dependencies
+
+- **Database Schema**: Managed by an external web application using better-auth
+- **User Management**: Handled by the external web application
+- **Session Creation**: Initial sessions created by the external web application
+
+## Getting Started
+
+### Prerequisites
+
+- Rust (latest stable)
+- PostgreSQL
+- Redis
+- Protobuf compiler
+
+### Building
+
+```bash
+cargo build --release
+```
+
+### Running
+
+Each service can be run individually:
+
+```bash
+# Auth Service
+cd auth-service && cargo run
+
+# Character Service
+cd character-service && cargo run
+
+# Database Service
+cd database-service && cargo run
+
+# Packet Service
+cd packet-service && cargo run
+
+# World Service
+cd world-service && cargo run
+```
+
+### Docker
+
+Each service includes a Dockerfile for containerized deployment.
+
+## Documentation
+
+Each service includes its own README.md with detailed documentation:
+
+- [Auth Service](auth-service/README.md)
+- [Character Service](character-service/README.md)
+- [Database Service](database-service/README.md)
+- [Packet Service](packet-service/README.md)
+- [World Service](world-service/README.md)
+- [Utils](utils/README.md)
+- [Launcher](launcher/README.md)
+
+## Testing
+
+Run tests for all services:
+
+```bash
+cargo test --all
+```
+
+## License
+
+This project is licensed under the Apache License 2.0 - see the [LICENSE](LICENSE) file for details.