Route hints may contain local fees instead of remote

[JssDWt]

If greenlight doesn't include the lsp route hint in a normal invoice (no channel open), we currently add the local routing fees in the route hint rather than the remote routing fees.

Relevant code here:
https://github.com/breez/breez-sdk/blob/2ff9646d03eac9f737834fdaeedc871d640d9649/libs/sdk-core/src/greenlight/node_api.rs#L1693-L1696

The code there has to be updated to use the remote policy (another call to the cln api listchannels api probably) to include the remote policies.
Another, additional, option can be to replace routing fees with the fees coming from lsp_information if the hint was not in the invoice originally, but it is included in the get_routing_hints call.