Removed voice & banner instructions from last step and added ssmlAnnouncements

[Trietes]

Issue

This PR is targetting to solve two of the issues mentioned in #4640. I've added simple voice ssmlAnnouncements to make the routing answers compatible with the navigation SDKs. I've also removed the voice and banner instructions from the last step since they are not required by the SDKs and just lead to confusing instructions on the screen.

Tasklist

• Add tests
• Add #fixes with the issue number that this PR addresses
• Update the changelog

[eikes]

I was not aware that the MapBox navigation SDK requires a ssmlAnnouncement but thank you for adding that.

I'll have to check what happens in the MapLibre navigation SDK when the last bannerInstructions and voiceInstructions are empty, I assume that it still works.

[Trietes]

I was not aware that the MapBox navigation SDK requires a ssmlAnnouncement but thank you for adding that.

Might also depend on the SDK version. In my case the app just crashed. I would guess mapbox navigation SDK set this as requiered at some point.

I'll have to check what happens in the MapLibre navigation SDK when the last bannerInstructions and voiceInstructions are empty, I assume that it still works.

Would be really cool if you can do this. At least directions API V5 of mapbox always returns empty lists in the last step. So I guess it shouldn't be a probelm for Maplibre. In case of Mapbox Navigation SDK it just leads to the strange side effects mentioned in the Issue.

[Trietes]

Just wanted to give a small update on this: I've it running now with an Maplibre app. Works fine on my side

[ianthetechie]

Yeah, I can confirm that some versions of the Mapbox-derived SDKs will crash without this. In our API middle layer for navigation at Stadia Maps, we added SSML <speak>{}</speak> wrapping exactly like this PR 😂

I'll have to check what happens in the MapLibre navigation SDK when the last bannerInstructions and voiceInstructions are empty, I assume that it still works.

This should work in every SDK I'm aware of (incl. newer ones like Ferrostar).

Anyone able to fix up the conflicts + get this merged? Seems pretty straightforward and low-risk to me :D

[Trietes]

Thanks for updating the branch! Should be ready for merging now.