[Refactor] Simplify tree-kill callback handling and remove redundant checks

[gonzaloriestra]

WHY are these changes introduced?

The internal helper functions adaptedTreeKill and killAll in packages/cli-kit/src/public/node/tree-kill.ts had redundant checks to verify whether callback was defined before calling it. However, the callback parameter is non-optional in both function signatures and treeKill always supplies a callback (defaulting to a log fallback if none is provided). Removing these redundant checks makes the file cleaner, simpler, and easier to maintain.

WHAT is this pull request doing?

• Removed redundant if (callback) checks in both adaptedTreeKill and killAll.
• Simplified the control flow using early returns.
• Added appropriate eslint-disable directive to satisfy custom ESLint rules regarding catch blocks without rethrows.

How to test your changes?

CI

Post-release steps

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes
• I've considered analytics changes to measure impact
• The change is user-facing — I've identified the correct bump type (patch for bug fixes · minor for new features · major for breaking changes) and added a changeset with pnpm changeset add

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PR created automatically by Jules for task 11173730342096362835 started by @gonzaloriestra

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