Syntax for constructing TaskTree should be enhanced to used in an easier way

Currently we have to Constructor each and every TaskNode and explicitly add it to a parent using 'AddChild'. That affects the readability and maintenance

Start by reading the TaskTree and TaskNode construction flow, especially how AddChild is currently used. The issue does not define the proposed syntax or acceptance criteria, so first establish the desired construction API and how its behavior should compare with explicit child creation and attachment.

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