[Draft] Bridges and roads autobuild inappropriately

[Matthew]

NB: This is a draft post. I am experimenting with this.

The industry road autobuilder (which is a great addition to the game!) just built a road that had two flaws:
(a) It had two x one-height bridges over sea tiles, which blocked ships (there was actually a ship stuck underneath  !):



(b) The autobuilder connected to the wider road network at a private way, even though they was a public road right next to the new industry.

(Try to get reproducible save)