Instant update narrow line color

[remcoder]

Color of narrow extrusion/travel lines is updated instantly.

The way I access the travel lines and extrusion lines in the scene:

• .userData a reserved object on 3d objects (meshes, groups) with a custom prop for 'lineType'.
• a function to 'query' the scene by traversing the scene graph and filtering on that lineType

[github-actions]

Visit the preview URL for this PR (updated for commit 835a3f5):

https://gcode-preview--pr313-feature-instant-upda-i9hrq75d.web.app

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