Refactor password handling in EmailAccountDto

Replaced the `EncryptedPassword` property in `EmailAccountDto` with `Password` and `PasswordEncrypted` to support both plain text and encrypted passwords. Updated `LimilabsEmailService` to use the new properties, checking the `PasswordEncrypted` flag to determine whether decryption is needed.

src/DigitalData.EmailProfiler.Infrastructure/Services/LimilabsEmailService.cs

@@ -91,7 +91,8 @@ public class LimilabsEmailService(
         }
         else
         {
-            var password = encryptionService.Decrypt(_smtpAccount.EncryptedPassword!);
+            var password = _smtpAccount.PasswordEncrypted ? encryptionService.Decrypt(_smtpAccount.Password) : _smtpAccount.Password;
+
             smtp.Login(_smtpAccount.Username, password);
         }