lnd_channels_open_balance_sat not including channel reserve

[SeverinAlexB]

The lnd_channels_open_balance_sat metrics only includes the local_balance shown in lncli listchannels and does not include the local_chan_reserve_sat. This leaves 1% of the funds missing.

[bitromortac]

This only passes through values from https://lightning.engineering/api-docs/api/lnd/lightning/channel-balance/index.html, where the reserve is probably not included. The question is whether it should be, or if we need to add a different metric to track how much funds are in the reserve?

[SeverinAlexB]

I guess to guarantee backwards compatibility, it should be a new metric?