fix: Improve labeling of line segments (#54)

Gets all of Joyce through Book V working.

Reviewed-on: #54
Co-authored-by: Glen Whitney <glen@studioinfinity.org>
Co-committed-by: Glen Whitney <glen@studioinfinity.org>

src/adapptlet.civet

@@ -378,7 +378,8 @@ function jToG(
                   when 'line'
                      (`Midpoint(${name})`
                       + ` + Rotate(Direction(${name})`
-                      +    `*Length(${name})*0.02, pi/2)`)
+                      +    `*Length(${name})*0.025/Length(Direction(${name})),`
+                      +    `pi/2)`)
                   when 'circle'
                      (`Center(${name})`
                       + ` + Radius(${name})*Vector((12/13,5/13))*1.03`)