Artifacts at tile Boundaries / Debug Tiles

Nobody has claimed this yet.

For edges located directly at tile boundaries, there seem to be some clipping issues. These should be addressed for the official release of transit.

An example of the issue can be seen here:

The same location zoomed out to the next level:

This shows that the data is there, but it does not show correctly.

Link for local debug frontend: [link](http://0.0.0.0:8000/#15.54/37.7329/-122.4206)

The bug itself could be located at any part that is related to clipping:

- clip box using boost geometry (see [here](https://github.com/mapbox/directions-transit/blob/187941019fdbacf84b9b0fe29ff8fefff3e68686/src/tool/container/mapbox_vector_tile.cpp#L84) and [here](https://github.com/mapbox/directions-transit/blob/187941019fdbacf84b9b0fe29ff8fefff3e68686/src/tool/container/mapbox_vector_tile.cpp#L260))
- bounding box (see [here](https://github.com/mapbox/directions-transit/blob/187941019fdbacf84b9b0fe29ff8fefff3e68686/src/tool/container/mapbox_vector_tile.cpp#L322) and [here](https://github.com/mapbox/directions-transit/blob/187941019fdbacf84b9b0fe29ff8fefff3e68686/src/geometric/bounding_box.cpp#L20) which is the most likely culprit

In an extended effort, the sizes of these bounding boxes could be tuned to not over-sample what we look at.

Start with the clipping and bounding-box code in src/tool/container/mapbox_vector_tile.cpp, especially the referenced lines 84, 260, and 322, then inspect src/geometric/bounding_box.cpp at line 20. Reproduce the boundary artifact using the linked local debug frontend and compare the affected tile with the zoomed-out view. Done means edges at tile boundaries render without clipping artifacts.

Written by the indexing model from the issue text.