Draft: Change archDimTracker text position depending on distance and scale values

[marioalexis84]

When the size of the text is similar to or greater than the length of the aid dimension line, there is an annoying overlap of both that makes reading difficult.
This change prevents this behavior by moving the text to an external position when necessary.
Also, avoid accessing inventor node fields on each function call acording to https://forum.freecadweb.org/viewtopic.php?f=10&t=26784&start=30#p219409

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