include rulers in worksheet

Is it possible to include rulers on top and left sides of worksheet?

There is no ruler.

You can have rough visual clues for distances with grids https://librecad.readthedocs.io/en/latest/ref/draw-prefs.html#grid.
You can also get coordinates of pointer in the status bar.

I once tried to add a ruler to v2, but the work needed turned out to be much more than expected.

The alternative, try some screen ruler, like kruler.

It's also possible to use fixed view and printing scales, but it's not so intuitive.