Refactor SewUpAction and its tests to Kotlin (CATROID-1586)

[harshsomankar123-tech]

Description

This PR refactors the SewUpAction class and its corresponding instrumentation tests from Java to Kotlin.

Reference: CATROID-1586 (https://catrobat.atlassian.net/browse/CATROID-1586)

Key Changes

• SewUpAction.kt:
  • Converted from SewUpAction.java.
  • Implemented Kotlin null-safety features, replacing potential NPEs with safe calls (?.) and explicit RuntimeException throws for critical null states.
  • Used idiomatic Kotlin features like lateinit, apply, and companion object.
  • Updated copyright year to 2026.
• SewUpActionTest.kt:
  • Renamed from SewUpTest.java as per Jira instructions.
  • Converted to Kotlin with full null-safety support (removed !! operators and handled nullability correctly).
  • Standardized test setup using lateinit var.
  • Updated copyright year to 2026.

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[harshsomankar123-tech]

@dorianpercic @reichli PTAL
Thanks!