Feat: Add prod+dev environment configuration and improve shutdown handling

## Changes - Added environment-specific configuration loading (.env for prod, dev.env for dev) - Implemented graceful shutdown handling for the backend server - Added logging configuration with different log levels - Configured Redis and PostgreSQL connection initialization - Renamed docker compose <https://docs.docker.com/compose/intro/compose-application-model/#the-compose-file> ## Implementation Details - Added environment detection using `RUST_ENV` variable in [`main.rs`](backend/src/main.rs) - Implemented graceful shutdown signal handling in [`utils.rs`](backend/src/utils.rs) - Set up tracing subscriber for structured logging with configurable levels - Added connection pool initialization for both Redis and PostgreSQL with proper error handling ## Related Configuration - Updated [Dockerfile](Dockerfile) to support production builds - Added Docker Compose service definitions in [compose.yaml](compose.yaml) - Added development instructions in [README.md](README.md) for running without Docker ## Testing Notes - Verified graceful shutdown with Ctrl+C signal - Tested database connections in both production and development environments - Confirmed logging works at different levels (DEBUG, INFO, WARN, ERROR)