Access map data layers through an API gateway

[claustres]

No built-in behaviour, should be based on e.g. GATEWAY env var on the backend:

• [x] generate a dedicated JWT to access the API gateway on login and store it in frontend
• [x] update layer url setup to insert the JWT in map component
• [x] update layer url setup to insert the JWT in globe component
• [x] remove API gateway token on logout in frontend
• [x] update default catalog layers definition
• [x] make API gateway JWT configurable

The frontend code should only use the gateway if the backend generates a token for it.

[claustres]

Because Cesium builds the final URL of tile sources by its own starting from a base URL + extension (see https://cesium.com/docs/cesiumjs-ref-doc/OpenStreetMapImageryProvider.html?classFilter=openst) we were not able to update the base URL with the token without breaking it. For now we use a "hack" by adding it to the extension instead but this should be enhanced.

[claustres]

As Kano can be embedded and used by different applications in a SSO scenario, https://github.com/kalisio/kano/issues/92 will be useful to allow to generate API gateway tokens with different configurations based on the provider selected by the user to connect. Indeed, once connected through the provider the user profile has a provider object attached.

This means that eg in Cognito we need:

• a different identity provider per embedding application
• a different application client per embedding application, enabling only the previous identity provider

From the kano point of view this will be see as different providers having different names anyway so that a custom generation process can take place based on this name.