Add API endpoints for stations

[ston1x]

• GET /stations/ - list of all stations
• GET /stations/:id - detailed info for a particular station

[roata]

It would be valuable. However, at this point we have no information about stations. In my opinion, the starting point should be the design of a data structure where this info is kept and how these structures relate to other entities.

For example

• stations are an ordered list
• some stations belong to several routes

A lot of this information can be taken from OpenStreetMaps, but before we do that - we need to make a plan about what to do with it.