Document Azure SQL minimum TLS 1.2 requirement

[Copilot]

Azure is retiring the MinTLS = None option on Azure SQL Database and SQL Managed Instance after 31 July 2026, enforcing TLS 1.2 and rejecting unencrypted connections.

Impact analysis

• App uses Microsoft.EntityFrameworkCore.SqlServer 8.0.12 → Microsoft.Data.SqlClient 5.x, which negotiates TLS 1.2/1.3 and defaults Encrypt=True.
• The only in-repo connection string targets (localdb) for local dev.
• No code or runtime config change is required — the change is operational (Azure portal) and informational (deployment connection string).

Changes

• README.md — new "Azure SQL: minimum TLS version" subsection under Infrastructure setup → Database covering:
  • The Azure-side action: set Minimum TLS Version to 1.2 on the SQL server / Managed Instance, with links to the official Microsoft docs.
  • Recommended explicit connection-string flag for the deployment environment, e.g.:

    Server=tcp:<server>.database.windows.net,1433;Database=NRZMyk;User Id=nrzmyk;******;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;
    

  • Note that no redeploy is needed once the server is raised to TLS 1.2, since the client already uses encrypted connections by default.