[SWF Diagram Editor] Show condition names, instead of expressions, when possible

Switch branches are anonymous and the different color of the default branch is not easy to recognize.

In order to provide some insights on the conditions which make trigger the branch execution, the graphical notation (SVG graph) has to include the label with the name of the condition (if present).

Moreover, it would be even clearer if, by hovering the mouse over the branch, a pop-up displayed the condition.

Expected Result

Default condition branch for switch branches should have color: #12DE70 and all branches should be thicker and have STROKE_WIDTH=2.

If data condition has parameter name than it should be displayed over the connection. Otherwise parameter condition should be used.

Decrease the arrow header size: width=8, height=12

Not a goal

Interaction with the branch to see the full condition value will be covered in KOGITO-7072.