Align with GBFS/TOMP geoJSON format

Is your feature request related to a problem? Please describe.

See https://github.com/TOMP-WG/TOMP-API/issues/485

It is not really a problem, but it's more about efficiency and ease of implementation. If the area endpoints in GBFS, MDS and TOMP could be alike (preferably geoJSON), the information could be published by the city, consumed by the TO (and shown in their app), published again by the TO (using GBFS/TOMP) and consumed directly by the MP (and again, shown in their app). The only thing that has to be taken into account, is that the rules that MDS (or maybe even CDS) use, are not all needed by the end users of the apps.

Describe the solution you'd like

the policy endpoint should produce geoJSON, that the Transport operators (TO) and the MaaS Service Providers can use in their apps (in a filtered way). In the current situation platforms that publish MDS (like Vianova) offer this service (transforming to geoJSON).

Is this a breaking change

• Yes, breaking: the policy and geography endpoints will be merged and formatted in a different way.

Impacted Spec

• policy

Describe alternatives you've considered

Use the geography endpoint to produce a complete geoJSON and refer to rules in the policy endpoint.

Review the current policy and geography endpoints and the linked TOMP-API issue 485 first. Define how the endpoints would be merged or related while preserving the needed policy rules, then verify that the resulting output is GeoJSON usable by transport operators and MaaS service providers without the proposed breaking-change scope remaining ambiguous.