feat: Refactor API structure and implement core functionalities

- Updated requirements to include asyncpg, pyyaml, aiofiles, and httpx.
- Modified schema.sql to add 'tipo_pasto' column in 'pasti' table.
- Created .gitignore file to exclude unnecessary files and directories.
- Added README.md for API implementation details and directory structure.
- Introduced config.yaml for centralized configuration management.
- Implemented core modules for database management, authentication, and exception handling.
- Developed models for 'pietanze', 'pasti', and 'prenotazioni' with validation.
- Created routes for CRUD operations on 'pietanze' with pagination and filtering.
- Established logging and error handling mechanisms throughout the application.
- Set up FastAPI application with CORS and health check endpoint.

api/core/database.py

@@ -0,0 +1,57 @@
+import asyncpg
+import yaml
+from typing import Optional
+import logging
+
+logger = logging.getLogger(__name__)
+
+class DatabaseManager:
+    def __init__(self):
+        self.pool: Optional[asyncpg.Pool] = None
+        
+    async def initialize(self, config: dict):
+        """Initialize database connection pool"""
+        try:
+            self.pool = await asyncpg.create_pool(
+                host=config['host'],
+                port=config['port'],
+                database=config['name'],
+                user=config['user'],
+                password=config['password'],
+                min_size=config.get('pool_min_size', 5),
+                max_size=config.get('pool_max_size', 20),
+                max_queries=config.get('pool_max_queries', 50000),
+                max_inactive_connection_lifetime=config.get('pool_max_inactive_connection_lifetime', 300.0)
+            )
+            logger.info("Database pool initialized successfully")
+        except Exception as e:
+            logger.error(f"Failed to initialize database pool: {e}")
+            raise
+    
+    async def close(self):
+        """Close database connection pool"""
+        if self.pool:
+            await self.pool.close()
+            logger.info("Database pool closed")
+    
+    async def execute_query(self, query: str, *args):
+        """Execute a query and return results"""
+        async with self.pool.acquire() as connection:
+            return await connection.fetch(query, *args)
+    
+    async def execute_one(self, query: str, *args):
+        """Execute a query and return single result"""
+        async with self.pool.acquire() as connection:
+            return await connection.fetchrow(query, *args)
+    
+    async def execute_command(self, query: str, *args):
+        """Execute a command (INSERT, UPDATE, DELETE)"""
+        async with self.pool.acquire() as connection:
+            return await connection.execute(query, *args)
+
+# Global database manager instance
+db_manager = DatabaseManager()
+
+async def get_database():
+    """Dependency for getting database connection"""
+    return db_manager