// Package postgres provides a pgx-backed PostgreSQL client with launcher and health integration.
//
// Usage:
//
//	db := postgres.New(logger, cfg)
//	lc.Append(db)
//	r.Get("/health", health.NewHandler(logger, db))
//
// The component manages a pgxpool connection pool, implements launcher lifecycle hooks,
// and satisfies health.Checkable (priority: critical).
//
// Use [NewUnitOfWork] to wrap operations in a transaction:
//
//	uow := postgres.NewUnitOfWork(logger, db)
//	uow.Do(ctx, func(ctx context.Context) error {
//	    exec := db.GetExecutor(ctx) // returns the active transaction
//	    _, err := exec.Exec(ctx, "INSERT ...")
//	    return err
//	})
package postgres