Refactor node structure. Replace nodes in parallel_for and parallel_reduce

[pavelkumbrasev]

Description

Refactor node structure to reuse it latter for scalability improvements in the library. E.g., #1310

Fixes # - issue number(s) if exists

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• bug fix - change that fixes an issue
• new feature - change that adds functionality
• tests - change in tests
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• documentation - documentation update

Tests

• added - required for new features and some bug fixes
• not needed

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Breaks backward compatibility

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