fix: Sass if() function deprecation warning in Sass 1.95.0+

[Copilot]

Proposed changes

Sass 1.95.0+ deprecates the if() function syntax with comparison operators. This causes deprecation warnings when building the project:

Deprecation Warning [if-function]: The Sass if() syntax is deprecated in favor of the modern CSS syntax.

Replaced deprecated if() with @if/@else control structure in arr-join() function:

Before:

$result: if(
    $i != list.length($list),
    $result#{$e}#{$glue},
    $result#{$e}
);

After:

@if $i != list.length($list) {
    $result: $result#{$e}#{$glue};
} @else {
    $result: $result#{$e};
}

Functionally equivalent, eliminates deprecation warning.

Types of changes

• Bugfix (non-breaking change that fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (improvements to existing components or architectural decisions)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Further comments

Single file change in packages/components/src/styles/internal/_stack-components.scss. Modern @if/@else syntax is the recommended approach for conditional logic in Sass and maintains compatibility across Sass versions.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>deprecation warning sass</issue_title>
<issue_description>### Which generators are affected?

• All
• HTML
• React
• Angular
• Vue
• Web components
• Power Apps

Reproduction case

I updated DB UI to version 4.2.3 and we use SASS version 1.95.0 in our project. After the update I got a deprecation warning. See Screenshot below.

Expected Behaviour

Not to have the deprecation warning.

Screenshots

Browser version

None

Add any other context about the problem here.

No response

Which DB business unit do you work for?

DB Systel GmbH (please name your customer below)

”DB Systel” please enter your customer / ”other” please enter your area or business unit.

No response

What project are you working on?

IGA</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes deprecation warning sass #5606

---

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🔭🐙🐈 Test this branch here: https://design-system.deutschebahn.com/core-web/review/copilot/fix-deprecation-warning-sass

[changeset-bot]

🦋 Changeset detected

Latest commit: dfc01fd

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 9 packages

Name	Type
@db-ux/core-components	Patch
@db-ux/ngx-core-components	Patch
@db-ux/react-core-components	Patch
@db-ux/wc-core-components	Patch
@db-ux/v-core-components	Patch
@db-ux/core-foundations	Patch
@db-ux/core-stylelint	Patch
@db-ux/core-migration	Patch
@db-ux/agent-cli	Patch

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