Disallow update of any features that are defined by LND (since
just updating the feature, but not the functionality will result in
strange behavior). All known feature bits should be toggled using
protocol config options.
This fixes an issue where if one tries to unset a feature like anchors,
and other feature depend on it, then `lnd` fails to start as it realizes
that its dependnacy set is inconsistent.
Fixes https://github.com/lightningnetwork/lnd/issues/6002
This commit introduces a feature.Manager, which derives feature vectors
for various contexts within the daemon. The sets can be described via a
staticly compiled format, which makes any runtime adjustments to the
feature sets when the manager is initialized.
