Update Authentication Project Template documentation for new add-auth navigation template flow

[georgianastasov]

Task type

• New topic / component documentation
• Update existing topic (new release, API change, new feature)
• Add missing platform variant (Angular / React / WebComponents / Blazor)
• Improve existing content (clarity, examples, structure)
• Add or update code samples
• Other

Platform(s)

• Angular
• React
• WebComponents
• Blazor
• All platforms

Description

Update the existing Angular Authentication Project Template documentation:

https://www.infragistics.com/products/ignite-ui-angular/angular/components/general/cli/auth-template

The current topic describes authentication as a standalone project template, using side-nav-auth. This should be updated to match the new CLI/Schematics template flow where authentication is offered as an additional option after selecting a supported navigation template.

The documentation should explain the new flow:

1. Select project type.
2. Select a base project template:
   • Empty Project
   • Side Navigation
   • Side Navigation Mini
3. If Side Navigation or Side Navigation Mini is selected, the CLI/Schematics should ask whether authentication should be added.
4. If Empty Project is selected, the authentication prompt should not be shown.

The topic should also clarify that authentication is now an add-on for supported navigation templates, not only a separate standalone Side Navigation with Authentication template.

The documentation should cover both supported generated auth variants:

Side Navigation + Authentication
Side Navigation Mini + Authentication

The existing authentication content should also be reviewed and updated where needed to match the current generated template structure.

The command examples should be reviewed and updated. If direct template generation with hidden auth template IDs is still supported, document it clearly as an advanced/direct usage option. Otherwise, update the topic to focus on the interactive add-auth flow.

Acceptance criteria

• The topic explains the new interactive template selection flow.
• The topic clearly states that authentication is offered only after selecting Side Navigation or Side Navigation Mini.
• The topic clearly states that Empty Project does not show the authentication option.
• The topic covers both generated variants:
  • Side Navigation + Authentication
  • Side Navigation Mini + Authentication
• Existing screenshots are reviewed and replaced if they no longer match the new flow or updated generated UI.
• CLI and Schematics command examples are updated to match the new behavior.
• Direct template usage is documented only if it remains officially supported.

Related resources

Existing documentation topic: https://www.infragistics.com/products/ignite-ui-angular/angular/components/general/cli/auth-template

Related CLI/template issue: IgniteUI/igniteui-cli#1724
Related CLI/template PR: IgniteUI/igniteui-cli#1725