[2515] fix configuration

[strongmindsaln]

KITOS Pull request template

Description

This pull request updates SMTP configuration handling to support authentication and SSL more robustly. The main changes add support for SMTP username and password in the SingleThreadedMailClient, ensure these credentials are used when configuring the mail client, and improve the handling of the EnableSsl and logging settings.

SMTP Authentication and Configuration:

• Updated the SingleThreadedMailClient constructor to accept optional userName and password parameters and set SmtpClient.Credentials if provided, enabling SMTP authentication.
• Modified dependency injection registration in KitosServiceRegistration.cs to read UserName and Password from configuration and pass them to the mail client.

Configuration and Deployment:

• Changed appsettings.json default for Smtp:EnableSsl to "true" to improve security.
• In PreparePackage.ps1, now sets Serilog.MinimumLevel.Default instead of Serilog.MinimumLevel and ensures Smtp.EnableSsl is set from the environment if provided.

Minor improvements:

• Added missing using System.Net; in SingleThreadedMailClient.cs to support credential assignment.

Checklist

The following procedure dictates the steps needed before a Pull request can be merged into master.

• Implement:
  All requirements are implemented and unit tests are green

• Merge master into branch / rebase with master:
  Make sure you are testing your changes and how they co-exist with the latest version of master

• Green on integration:
  All integration tests are green on integration

• Add a description
  Under "Description" above, explain what was changed in this branch, and WHY it was changed

• Request review:
  Tag whomever you wish to review your code

• Review completed:
  Reviewer ticks this box when review comments have been submitted

• Changes:
  PR owner and reviewer agrees on which changes must be made and the changes are committed.

• Merge master into branch / rebase with master:
  Make sure you are testing your changes and how they co-exist with the latest version of master

• Green on integration:
  All integration tests are green on integration

[Copilot]

Pull request overview

Updates the deployment packaging script to correctly apply runtime configuration into appsettings.json during packaging, aligning generated JSON structure with the application’s expected configuration shape.

Changes:

• Conditionally sets Smtp.EnableSsl from environment when provided.
• Writes Serilog log level to Serilog:MinimumLevel:Default instead of overwriting MinimumLevel.