New module that judges the earnings track record of nodes we had
channels with before, so channel-open candidate selection can prefer
proven earners. The metric is TRAL (annualized net return on
liquidity, in basis points), the same metric as
contrib/clboss-forwarding-stats: net earnings from the EarningsTracker
daily buckets, divided by the average balance and the observed
operational days from the FeeMonitor records, annualized. Both
sources persist after a channel closes, which is exactly the case this
serves: candidates whose previous channel with us is gone.
Operational days count only in-window records (roughly one per hour
while a channel exists), so a channel that overlapped the window
partially is annualized over its actual operating time. Averaging the
balance per-record rather than sample-and-hold over wall-clock time
keeps a mid-window close from diluting the average.
Verdicts: keeper (TRAL at or above threshold), no-record (no or
insufficient history), underperformer (history below threshold).
Three dynamic options (runtime-settable via setconfig):
clboss-candidate-record-window-days (180),
clboss-candidate-keeper-tral-bps (50),
clboss-candidate-min-record-days (7).
A clboss-track-record nodeid command shows the verdict and its inputs
for one node, plus the current option values, for tuning at runtime.
