Refactor: Extract shared addCopyingAndReturn helper for control flow transformations

[LalitNarayanYadav]

Addresses #8694

Changes:

• Extracted a shared addCopyingAndReturn helper used by both IfStatement and ForStatement handlers
• Introduced a sourcePrefix parameter to unify source expression construction:
  • null for IfStatement (direct variable access)
  • 'vars' for ForStatement (loop variable container)
• Removed duplicated inline implementations from both handlers
• Updated call sites to use the shared helper

This refactor reduces duplication and improves maintainability without changing behavior. All existing tests pass.

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Screenshots of the change:

N/A (non-visual refactor)

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PR Checklist

• npm run lint passes
• Inline reference is included / updated
• Unit tests are included / updated

[p5-bot]

Continuous Release

CDN link

• https://raw.esm.sh/pr/p5@727809f/lib/p5.min.js

Published Packages

• https://pkg.pr.new/p5@727809f

Commit hash: 0de66f7

Previous deployments

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This is an automated message.

[davepagurek]

Thanks, looks good!