Sketch special paths in the site

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Certain tasks can benefit from allowing users to sketch specific paths that aren't part of navigation but simply part of a task or a process.

For example, cleaning tasks will often have the robot travel a zig-zagging path across the floor. It would be helpful if users could sketch that zig-zag in the site editor and include it in the nav graph config file as a resource that the fleet adapter can reference. Sketching paths may also be helpful for complex docking procedures or other types of tasks.