Merge core track sections into TopoTrackSection

[Khoyo]

Description and goal

The goal is to avoid the edge case of signals/detector pairs on the edge of a tracklink.

Acceptance criteria

• [ ] create a new interface to track merged tracksections
• [ ] merge track sections present on a link switch
• [ ] build TrackChunks on these new TopoTrackSection
• [ ] trigger an error when signals or detectors are on non-link switches in core

[Castavo]

@Khoyo is this still relevant