refact(Polar): make all properties SetAccess private

+af_tools/@Polar/Polar.m

@@ -68,7 +68,7 @@ classdef Polar
     % Issues: https://gitlab.uliege.be/am-dept/matlab_airfoil_toolbox/-/issues
     % ----------------------------------------------------------------------------------------------
 
-    properties
+    properties (SetAccess = private)
         reynolds (1, :) double {mustBeNonnegative} % Rynolds number, [-]
         mach     (1, :) double {mustBeNonnegative} % Mach number, [-]
         nCrit    (1, :) double {mustBeNonnegative} % nCrit number, [-]
@@ -76,9 +76,7 @@ classdef Polar
         cl       (:, :) double {mustBeReal} % Lift coefficient, [-]
         cd       (:, :) double {mustBeReal} % Drag coefficient, [-]
         cm       (:, :) double {mustBeReal} % Moment coefficient, [-]
-    end
 
-    properties (SetAccess = private)
         Ext   = struct('aoa', [], 'cl', [], 'cd', [], 'cm', []) % Extended polar data
         Stall = struct('aoa', [], 'cl', [], 'cd', []) % Stall point data
         Zero  = struct('aoa', [], 'cd', []) % Zero-lift point data