freezeCheck: only count spendable channels in lnbalance

Previous calc summed our_amount_msat across every channel regardless of
state, including ONCHAIN (channels that have been closed and are waiting
for the on-chain sweep). Those funds are not actually usable for
lightning sends, but were inflating lnbalance — and therefore inflating
${type}:limit — by the locked-up amount. With several closed channels
pending sweep, the effective threshold floor was tens of megasats lower
than the configured lightning:threshold suggested.

Filter to CHANNELD_NORMAL (and CHANNELD_AWAITING_SPLICE so an in-flight
splice doesn't briefly pin the limit to zero).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

0 files changed, 0 insertions, 0 deletions