Add pool pre-ping check and max_lifetime=300 to AsyncConnectionPool

Adds check=AsyncConnectionPool.check_connection to detect and discard
dead connections before use (equivalent to pool_pre_ping=True), and
max_lifetime=300 to recycle connections older than 5 minutes (equivalent
to pool_recycle=300). This fixes SSL connection closure errors on
NeonDB's free tier.

Co-authored-by: MattiaFailla <11872425+MattiaFailla@users.noreply.github.com>

Author: Copilot

src/python_italy_bot/db/__init__.py

@@ -26,7 +26,12 @@ async def create_repository(database_url: str | None) -> AsyncRepository:
     if database_url and database_url.startswith("postgresql"):
         from psycopg_pool import AsyncConnectionPool
 
-        pool = AsyncConnectionPool(database_url, open=False)
+        pool = AsyncConnectionPool(
+            database_url,
+            open=False,
+            check=AsyncConnectionPool.check_connection,
+            max_lifetime=300,
+        )
         await pool.open()
         return PostgresRepository(pool)
     return InMemoryRepository()