Validation fixes, finished application creation, added required char (*) for required fields

SchengenVisaApi/ApplicationLayer/Constants.cs

@@ -0,0 +1,13 @@
+using System.Text.RegularExpressions;
+
+namespace ApplicationLayer
+{
+    public static class Constants
+    {
+        public readonly static Regex EnglishWordRegex = new("^[a-zA-Z]*$");
+
+        public readonly static Regex EnglishPhraseRegex = new(@"^[a-zA-Z№0-9?><;,{}[\]\-_+=!@#$%\^&*|']*$");
+
+        public readonly static Regex PhoneNumRegex = new(@"^[\+]?[(]?[0-9]{3}[)]?[-\s\.]?[0-9]{3}[-\s\.]?[0-9]{4,6}$");
+    }
+}