[FTJ] - CS Templates should be checked + Handle Heartbeat for Schneider

[LucasBrazi06]

Issue:
Invalid params are filtered and not saved in the DB and the user doesn't know about it!
Schneider OCPP heartbeat param is not following the spec: HeartBeatInterval instead of HeartbeatInterval thus the param is filtered in the backend and saved in the DB without letting know the user!

Todo:
Check if the templates are correct after the Json schema validation in the backend
If different, return an HTTP error code to the user
Handle the error in the UI + display a proper message
Add the HeartBeatInterval in the schema and auth for Schneider.

Done in the corresponding repos
https://github.com/charge-angels/ca-ev-dashboard
https://github.com/charge-angels/ca-ev-server

Nb: I cannot create a PR between the two repos because of too many changes and no time at the moment to create a PR on yours