UI: lanes and road edges not drawn well over ecamera view

### Describe the bug

This is a relatively minor cosmetic issue.

Lane lines and road edges are recognized and drawn well in the normal fcamera view, which is used for stock ACC and chill OP long. But when driving at low speed in experimental mode, looking at the ecamera view, they are drawn with an inward offset and the angles aren't right.

### Provide a route where the issue occurs

`f39cf149898833ff/0000000e--5016d7b031`

### openpilot version

d02f78a59caa5a5734e5ce10893c2fbdc1cef859 with some VW controls experiments

### Additional info

**Good fcamera view**

**Same road, bad ecamera view**

Replay route f39cf149898833ff/0000000e--5016d7b031 in experimental low-speed mode and compare the ecamera view with the normal fcamera view. The issue names no files, tests, or code entry points, so trace the UI rendering path for lane lines and road edges; done means their offsets and angles match the recognized road geometry in ecamera.

Written by the indexing model from the issue text.